Merge pull request 'feat(translation): 8h sweep + drain button + detection probe (#1376)' (#207) from dev into main

Throughput: translate_posts now runs every 8h (was daily) as the
steady-state cadence for newly-imported posts, and the Settings
"Translate now" button runs it in drain mode (run-until-done, no reset)
so one press clears the whole untranslated backlog instead of a single
300-post chunk. The interrupt/backoff re-enqueue now preserves the drain
flag so a bulk drain resumes cleanly after an Interpreter restart.

Misdetection groundwork: surface the detector's confidence from the
Interpreter client (it was in the detectedLanguage payload but discarded)
and add a read-only "Test translation" box — POST /settings/translation/
probe + TranslationCard UI — that shows detected language + confidence +
engine + result for pasted text, without saving. Lets the operator see
why a short/abbreviation-heavy English title gets mis-detected so the
detection guard (min-length + confidence floor) can be tuned from real
numbers. The guard itself follows once the mis-detected cases are probed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CgZP9v2otxVJymiYsnVuMy

alembic/versions/0083_post_translation.py

@@ -0,0 +1,73 @@
+"""post-text translation via Interpreter (milestone 143) — Post columns + settings
+
+Post gains the translated title/description + the detected source language,
+Interpreter engine_version (cache key), and translated_at — filled by the
+translate sweep. ImportSettings gains translation_enabled (OFF by default),
+interpreter_base_url (EMPTY — the operator sets their own, behind a reverse
+proxy), and translation_target_lang (en).
+
+Revision ID: 0083
+Revises: 0082
+Create Date: 2026-07-07
+"""
+from typing import Sequence, Union
+
+import sqlalchemy as sa
+from alembic import op
+
+revision: str = "0083"
+down_revision: Union[str, None] = "0082"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.add_column(
+        "post", sa.Column("post_title_translated", sa.Text(), nullable=True)
+    )
+    op.add_column(
+        "post", sa.Column("description_translated", sa.Text(), nullable=True)
+    )
+    op.add_column(
+        "post",
+        sa.Column("translated_source_lang", sa.String(8), nullable=True),
+    )
+    op.add_column(
+        "post",
+        sa.Column("translation_engine_version", sa.String(128), nullable=True),
+    )
+    op.add_column(
+        "post",
+        sa.Column("translated_at", sa.DateTime(timezone=True), nullable=True),
+    )
+    op.add_column(
+        "import_settings",
+        sa.Column(
+            "translation_enabled", sa.Boolean(), nullable=False,
+            server_default=sa.text("false"),
+        ),
+    )
+    op.add_column(
+        "import_settings",
+        sa.Column(
+            "interpreter_base_url", sa.Text(), nullable=False, server_default="",
+        ),
+    )
+    op.add_column(
+        "import_settings",
+        sa.Column(
+            "translation_target_lang", sa.Text(), nullable=False,
+            server_default="en",
+        ),
+    )
+
+
+def downgrade() -> None:
+    op.drop_column("import_settings", "translation_target_lang")
+    op.drop_column("import_settings", "interpreter_base_url")
+    op.drop_column("import_settings", "translation_enabled")
+    op.drop_column("post", "translated_at")
+    op.drop_column("post", "translation_engine_version")
+    op.drop_column("post", "translated_source_lang")
+    op.drop_column("post", "description_translated")
+    op.drop_column("post", "post_title_translated")

backend/app/api/gallery.py

@@ -145,6 +145,9 @@ async def similar():
         filters, _sort = _parse_filters()
     except (KeyError, ValueError):
         return jsonify({"error": "similar_to query param required"}), 400
+    # Explore passes exclude_wip=1 to also drop work-in-progress from the
+    # rabbit-hole; the gallery's own "similar" button omits it (keeps wip, #1274).
+    exclude_wip = request.args.get("exclude_wip") in ("1", "true", "True")
     # post_id is the exclusive post-detail view — not a similarity scope.
     # include_hidden is a gallery-browse flag; similar() has its OWN presentation
     # exclusion (a similarity-quality concern, #1274), so drop it here (#141).
@@ -154,7 +157,8 @@ async def similar():
     async with get_session() as session:
         svc = GalleryService(session)
         try:
-            images = await svc.similar(image_id=similar_to, limit=limit, **scope)
+            images = await svc.similar(
+                image_id=similar_to, limit=limit, exclude_wip=exclude_wip, **scope)
         except ValueError as exc:
             return jsonify({"error": str(exc)}), 400
     if images is None:

backend/app/api/settings.py

@@ -1,12 +1,24 @@
 """Settings API: import filters, system stats."""
 
+import asyncio
 import secrets
 
 from quart import Blueprint, jsonify, request
-from sqlalchemy import func, select
+from sqlalchemy import func, or_, select
 
 from ..extensions import get_session
-from ..models import AppSetting, Artist, ImageRecord, ImportBatch, ImportSettings, ImportTask, Tag
+from ..models import (
+    AppSetting,
+    Artist,
+    ImageRecord,
+    ImportBatch,
+    ImportSettings,
+    ImportTask,
+    Post,
+    Tag,
+    TaskRun,
+)
+from ..services import interpreter_client as ic
 
 settings_bp = Blueprint("settings", __name__, url_prefix="/api")
 
@@ -32,6 +44,9 @@ _EDITABLE_FIELDS = (
     "extdl_mediafire_enabled",
     "extdl_dropbox_enabled",
     "extdl_pixeldrain_enabled",
+    "translation_enabled",
+    "interpreter_base_url",
+    "translation_target_lang",
 )
 
 # Per-host external-download toggles — all plain booleans, validated uniformly.
@@ -69,6 +84,9 @@ async def get_import_settings():
         "extdl_mediafire_enabled": row.extdl_mediafire_enabled,
         "extdl_dropbox_enabled": row.extdl_dropbox_enabled,
         "extdl_pixeldrain_enabled": row.extdl_pixeldrain_enabled,
+        "translation_enabled": row.translation_enabled,
+        "interpreter_base_url": row.interpreter_base_url,
+        "translation_target_lang": row.translation_target_lang,
     })
 
 
@@ -128,6 +146,15 @@ async def update_import_settings():
     for tog in _EXTDL_TOGGLE_FIELDS:
         if tog in body and not isinstance(body[tog], bool):
             return jsonify({"error": f"{tog} must be a boolean"}), 400
+    # Translation (#143): base URL may be empty (feature off until set — no
+    # default host; the operator points it at their own Interpreter proxy).
+    if "translation_enabled" in body and not isinstance(
+        body["translation_enabled"], bool
+    ):
+        return jsonify({"error": "translation_enabled must be a boolean"}), 400
+    for key in ("interpreter_base_url", "translation_target_lang"):
+        if key in body and not isinstance(body[key], str):
+            return jsonify({"error": f"{key} must be a string"}), 400
     if "series_suggest_threshold" in body:
         v = body["series_suggest_threshold"]
         if not isinstance(v, (int, float)) or isinstance(v, bool) or v < 0 or v > 1:
@@ -270,3 +297,159 @@ async def rotate_extension_api_key():
             row.value = new_value
         await session.commit()
     return jsonify({"key": new_value})
+
+
+# --- Translation (#143): live status + manual "Translate now" --------------
+
+
+@settings_bp.route("/settings/translation/status", methods=["GET"])
+async def translation_status():
+    """For the Settings card: is it on, is a URL set, is the service reachable,
+    and how many posts still await translation. Health runs the sync client in a
+    thread so the event loop isn't blocked."""
+    translation_tasks = (
+        "backend.app.tasks.translation.translate_posts",
+        "backend.app.tasks.translation.retranslate_posts",
+    )
+    async with get_session() as session:
+        cfg = await ImportSettings.load(session)
+        untranslated = (await session.execute(
+            select(func.count(Post.id))
+            .where(Post.translated_source_lang.is_(None))
+            .where(or_(
+                Post.post_title.is_not(None), Post.description.is_not(None),
+            ))
+        )).scalar_one()
+        # Live progress: is a sweep running now, and what did the last one do?
+        # (run-until-done re-enqueues itself, so `active` stays true across a
+        # bulk re-translate; `last_run` surfaces a completed run's outcome.)
+        active = (await session.execute(
+            select(func.count(TaskRun.id))
+            .where(TaskRun.task_name.in_(translation_tasks))
+            .where(TaskRun.status == "running")
+        )).scalar_one()
+        last = (await session.execute(
+            select(TaskRun.task_name, TaskRun.status, TaskRun.finished_at)
+            .where(TaskRun.task_name.in_(translation_tasks))
+            .where(TaskRun.finished_at.is_not(None))
+            .order_by(TaskRun.finished_at.desc())
+            .limit(1)
+        )).first()
+    base_url = (cfg.interpreter_base_url or "").strip()
+    healthy = await asyncio.to_thread(ic.health, base_url) if base_url else False
+    return jsonify({
+        "enabled": cfg.translation_enabled,
+        "base_url_set": bool(base_url),
+        "healthy": healthy,
+        "untranslated_count": int(untranslated),
+        "active": int(active) > 0,
+        "last_run": {
+            "task": last[0].rsplit(".", 1)[-1],
+            "status": last[1],
+            "finished_at": last[2].isoformat() if last[2] else None,
+        } if last else None,
+    })
+
+
+@settings_bp.route("/settings/translation/test", methods=["POST"])
+async def translation_test():
+    """On-demand reachability check for a GIVEN Interpreter base URL (the Settings
+    'Test connection' button) — pings /v1/health without saving, so the operator
+    can verify a URL before enabling. Health runs in a thread (sync client)."""
+    body = await request.get_json()
+    base_url = ""
+    if isinstance(body, dict):
+        base_url = (body.get("base_url") or "").strip()
+    healthy = await asyncio.to_thread(ic.health, base_url) if base_url else False
+    return jsonify({"healthy": healthy})
+
+
+@settings_bp.route("/settings/translation/probe", methods=["POST"])
+async def translation_probe():
+    """Diagnostic for the Settings 'Test translation' box: translate a pasted
+    snippet WITHOUT saving anything, returning what Interpreter *detected*
+    (language + confidence) alongside the result. Lets the operator see why a
+    given string was (mis-)detected — e.g. a short English title flagged as
+    another language — so a detection guard can be tuned from real numbers.
+    Read-only: no post is touched. Uses the currently-saved base URL + target."""
+    body = await request.get_json(silent=True)
+    body = body if isinstance(body, dict) else {}
+    text = (body.get("text") or "").strip()
+    if not text:
+        return jsonify({"error": "provide text to translate"}), 400
+    async with get_session() as session:
+        cfg = await ImportSettings.load(session)
+    base_url = (cfg.interpreter_base_url or "").strip()
+    if not base_url:
+        return jsonify({"error": "no Interpreter base URL is set"}), 400
+    target = (cfg.translation_target_lang or "en").strip() or "en"
+    try:
+        res = await asyncio.to_thread(
+            ic.translate, [text], base_url=base_url, target=target,
+        )
+    except ic.InterpreterUnavailable as e:
+        return jsonify({"error": f"Interpreter unavailable: {e}"}), 503
+    except ic.InterpreterBadRequest as e:
+        return jsonify({"error": f"Interpreter rejected the request: {e}"}), 400
+    translations = res.get("translations") or []
+    return jsonify({
+        "target": target,
+        "detected_lang": res.get("detected_lang"),
+        "detected_confidence": res.get("detected_confidence"),
+        "engine": res.get("engine"),
+        "engine_version": res.get("engine_version"),
+        "translated": translations[0] if translations else None,
+    })
+
+
+@settings_bp.route("/settings/translation/run", methods=["POST"])
+async def translation_run():
+    """Enqueue the translate sweep now (the Settings 'Translate now' button).
+    Runs in drain mode — run-until-done — so one press chases the whole
+    untranslated backlog to zero rather than a single 300-post chunk."""
+    async with get_session() as session:
+        cfg = await ImportSettings.load(session)
+    if not cfg.translation_enabled or not (cfg.interpreter_base_url or "").strip():
+        return jsonify(
+            {"error": "translation is disabled or no base URL is set"}
+        ), 400
+    from ..tasks.translation import translate_posts
+
+    r = translate_posts.delay(drain=True)
+    return jsonify({"celery_task_id": r.id}), 202
+
+
+@settings_bp.route("/settings/translation/retranslate", methods=["POST"])
+async def translation_retranslate():
+    """Re-translate stored translations after a model change (m146). Body:
+    ``{"artist_id": <int>}`` aims at one artist; ``{"all": true}`` re-runs every
+    artist. ``all`` must be explicit so an empty/typo body can't wipe everything.
+    Clears the scoped translations and enqueues the run-until-done retranslate
+    sweep (the Interpreter cache re-translates on a changed model, is cache-fast
+    otherwise). Same enabled + base-URL guard as 'Translate now'."""
+    body = await request.get_json(silent=True)
+    body = body if isinstance(body, dict) else {}
+    artist_id = body.get("artist_id")
+    do_all = bool(body.get("all"))
+    if artist_id is None and not do_all:
+        return jsonify(
+            {"error": "provide artist_id, or all=true to re-translate everything"}
+        ), 400
+    if artist_id is not None:
+        try:
+            artist_id = int(artist_id)
+        except (TypeError, ValueError):
+            return jsonify({"error": "artist_id must be an integer"}), 400
+
+    async with get_session() as session:
+        cfg = await ImportSettings.load(session)
+    if not cfg.translation_enabled or not (cfg.interpreter_base_url or "").strip():
+        return jsonify(
+            {"error": "translation is disabled or no base URL is set"}
+        ), 400
+    from ..tasks.translation import retranslate_posts
+
+    # artist_id wins when both are sent; otherwise all=true → None (every artist).
+    artist_ids = [artist_id] if artist_id is not None else None
+    r = retranslate_posts.delay(artist_ids=artist_ids)
+    return jsonify({"celery_task_id": r.id}), 202

backend/app/celery_app.py

@@ -35,6 +35,7 @@ def make_celery() -> Celery:
             "backend.app.tasks.backup",
             "backend.app.tasks.admin",
             "backend.app.tasks.library_audit",
+            "backend.app.tasks.translation",
         ],
     )
     app.conf.update(
@@ -63,9 +64,20 @@ def make_celery() -> Celery:
             "backend.app.tasks.backup.*": {"queue": "maintenance_long"},
             "backend.app.tasks.admin.*": {"queue": "maintenance_long"},
             "backend.app.tasks.library_audit.*": {"queue": "maintenance_long"},
+            # Translation backfill hits the LLM (~1–6s/item) → the long lane so it
+            # never starves the quick self-healing sweeps (#143).
+            "backend.app.tasks.translation.*": {"queue": "maintenance_long"},
         },
         # Heavy ML tasks need fair dispatch — see ImageRepo's precedent.
         task_acks_late=True,
+        # Deploy graceful-shutdown safety: with acks_late, a task killed because
+        # it outran the container's stop-grace window (SIGKILL) is re-queued
+        # rather than silently lost. Safe because our long tasks are idempotent +
+        # chunked (translation per-post commit, downloads terminal-status, audits
+        # chunk) and the 5-min recovery sweeps re-drive anything left non-terminal
+        # — a re-run resumes cleanly and never corrupts. No redeliver-loop risk:
+        # heavy GPU work is tombstoned via gpu_queue, not run inline in a worker.
+        task_reject_on_worker_lost=True,
         worker_prefetch_multiplier=1,
         # Broker resilience (2026-06-24): a swarm overlay-network blip after a
         # redeploy left Redis healthy but transiently unreachable, and a worker
@@ -103,6 +115,11 @@ def make_celery() -> Celery:
                 "task": "backend.app.tasks.maintenance.cleanup_old_tasks",
                 "schedule": 86400.0,  # daily
             },
+            "cleanup-orphaned-temp-files": {
+                "task": "backend.app.tasks.maintenance.cleanup_orphaned_temp_files",
+                "schedule": 86400.0,  # daily — sweep .part/.partial left by a
+                # download/import killed mid-write (graceful-shutdown fallout)
+            },
             "train-heads-nightly": {
                 "task": "backend.app.tasks.ml.scheduled_train_heads",
                 "schedule": 86400.0,  # passive cadence; manual retrain stays available
@@ -161,6 +178,14 @@ def make_celery() -> Celery:
                 "task": "backend.app.tasks.ml.prune_presentation_reviews",
                 "schedule": 86400.0,  # retention: drop resolved review flags >30d
             },
+            "translate-posts-8h": {
+                "task": "backend.app.tasks.translation.translate_posts",
+                "schedule": 28800.0,  # every 8h: steady-state cadence for the
+                # trickle of newly-imported posts (no-op unless translation
+                # configured + healthy). One bounded 300-chunk per fire — the
+                # one-time backlog drains via the "Translate now" button
+                # (drain=True, run-until-done), not this sweep.
+            },
             "snapshot-head-metrics-daily": {
                 "task": "backend.app.tasks.maintenance.snapshot_head_metrics",
                 "schedule": 86400.0,

backend/app/models/import_settings.py

@@ -92,6 +92,21 @@ class ImportSettings(Base):
         Boolean, nullable=False, default=True, server_default="true",
     )
 
+    # -- Post-text translation via the Interpreter LAN service (milestone 143).
+    # Off by default with NO default host — it needs a reachable Interpreter
+    # service (the operator's, behind a reverse proxy), which not every install
+    # has; the operator sets the URL and flips it on. Empty base_url OR disabled
+    # → the translate sweep no-ops.
+    translation_enabled: Mapped[bool] = mapped_column(
+        Boolean, nullable=False, default=False, server_default="false",
+    )
+    interpreter_base_url: Mapped[str] = mapped_column(
+        Text, nullable=False, default="", server_default="",
+    )
+    translation_target_lang: Mapped[str] = mapped_column(
+        Text, nullable=False, default="en", server_default="en",
+    )
+
     @classmethod
     async def load(cls, session) -> ImportSettings:
         """The singleton settings row (id=1), via an async session."""

backend/app/models/post.py

@@ -47,6 +47,24 @@ class Post(Base):
     description: Mapped[str | None] = mapped_column(Text, nullable=True)
     attachment_count: Mapped[int | None] = mapped_column(Integer, nullable=True)
 
+    # -- Post-text translation (milestone 143). Filled by the translate_posts
+    # sweep via the Interpreter LAN service so viewing is instant.
+    # translated_source_lang is the DETECTED original language; "en" (or a
+    # passthrough) means nothing to translate and the *_translated columns stay
+    # NULL. engine_version keys the Interpreter cache — re-runs are ~1ms and a
+    # model upgrade re-translates instead of serving stale.
+    post_title_translated: Mapped[str | None] = mapped_column(Text, nullable=True)
+    description_translated: Mapped[str | None] = mapped_column(Text, nullable=True)
+    translated_source_lang: Mapped[str | None] = mapped_column(
+        String(8), nullable=True
+    )
+    translation_engine_version: Mapped[str | None] = mapped_column(
+        String(128), nullable=True
+    )
+    translated_at: Mapped[datetime | None] = mapped_column(
+        DateTime(timezone=True), nullable=True
+    )
+
     downloaded_at: Mapped[datetime] = mapped_column(
         DateTime(timezone=True), nullable=False, server_default=func.now()
     )

backend/app/models/tag.py

@@ -48,6 +48,10 @@ class TagKind(StrEnum):
 # content. `wip` is real art: only the training pipelines exclude it.
 SYSTEM_TAG_NAMES = ("wip", "banner", "editor screenshot")
 PRESENTATION_SYSTEM_TAGS = ("banner", "editor screenshot")
+# `wip` marks real-but-unfinished art. It's kept in the gallery's own "similar"
+# results (#1274), but the Explore rabbit-hole opts to hide it (exclude_wip) so a
+# browse doesn't keep surfacing work-in-progress (operator, 2026-07-08).
+WIP_SYSTEM_TAG = "wip"
 
 image_tag = Table(
     "image_tag",

backend/app/services/gallery_service.py

@@ -31,7 +31,7 @@ from ..models import (
     Tag,
     TagPositiveConfirmation,
 )
-from ..models.tag import PRESENTATION_SYSTEM_TAGS, image_tag
+from ..models.tag import PRESENTATION_SYSTEM_TAGS, WIP_SYSTEM_TAG, image_tag
 from .pagination import decode_cursor, encode_cursor
 from .tag_query import (
     fandom_join_alias,
@@ -715,6 +715,7 @@ class GalleryService:
         platform: str | None = None,
         untagged: bool = False, no_artist: bool = False,
         date_from: datetime | None = None, date_to: datetime | None = None,
+        exclude_wip: bool = False,
     ) -> list[GalleryImage] | None:
         """Visual "more like this": images near `image_id`'s SigLIP embedding
         (pgvector, HNSW-indexed — alembic 0036), then DIVERSIFIED so the result
@@ -751,14 +752,18 @@ class GalleryService:
         # Presentation images (banner / editor-screenshot system tags, #128)
         # cluster on UI chrome rather than content, so near any one of them
         # they'd fill the grid. Excluded from CANDIDATES only — the anchor
-        # itself may be a banner, and `wip` stays surfaced (real art; only
-        # the training pipelines exclude it).
+        # itself may be a banner. `wip` stays surfaced here by default (real art;
+        # only the training pipelines exclude it), but the Explore rabbit-hole
+        # passes exclude_wip to also drop work-in-progress (operator, 2026-07-08).
+        excluded_system_tags = PRESENTATION_SYSTEM_TAGS
+        if exclude_wip:
+            excluded_system_tags = (*PRESENTATION_SYSTEM_TAGS, WIP_SYSTEM_TAG)
         presentation = (
             select(image_tag.c.image_record_id)
             .join(Tag, Tag.id == image_tag.c.tag_id)
             .where(
                 Tag.is_system.is_(True),
-                Tag.name.in_(PRESENTATION_SYSTEM_TAGS),
+                Tag.name.in_(excluded_system_tags),
             )
         )
         stmt = stmt.where(

backend/app/services/interpreter_client.py

@@ -0,0 +1,152 @@
+"""Interpreter translation client (milestone 143) — a thin SYNC wrapper over the
+self-hosted Interpreter LAN service (LibreTranslate-compatible `/v1/translate`).
+
+Sync (requests) because the only caller is the sync celery translate sweep, and
+it mirrors FC's other platform clients. The service knows nothing about Curator —
+all Curator logic stays here. base_url is operator-configured (empty until set;
+behind a reverse proxy). Full API contract: Scribe note #1347.
+"""
+from __future__ import annotations
+
+from datetime import UTC, datetime
+from email.utils import parsedate_to_datetime
+
+import requests
+from requests.adapters import HTTPAdapter
+from urllib3.util.retry import Retry
+
+
+class InterpreterUnavailable(Exception):
+    """The translation engine is down / unreachable / draining — a connection
+    error, HTTP 429, or a 5xx (commonly 502/503/504 through a reverse proxy while
+    the service restarts). Retry later, don't drop the item. ``retry_after`` holds
+    the server's Retry-After hint in seconds when it sent one, so the caller can
+    back off exactly as long as it's asked to."""
+
+    def __init__(self, message: str, *, retry_after: float | None = None):
+        super().__init__(message)
+        self.retry_after = retry_after
+
+
+class InterpreterBadRequest(Exception):
+    """Bad request params (HTTP 400)."""
+
+
+def _url(base_url: str, path: str) -> str:
+    return f"{base_url.rstrip('/')}{path}"
+
+
+def _parse_retry_after(resp) -> float | None:
+    """Parse a Retry-After header (RFC 7231: delta-seconds or an HTTP-date) into
+    non-negative seconds, or None if absent/unparseable — so a gracefully-
+    draining Interpreter can tell Curator exactly how long to wait before it
+    tries again."""
+    raw = (resp.headers.get("Retry-After") or "").strip()
+    if not raw:
+        return None
+    try:
+        return max(0.0, float(int(raw)))       # delta-seconds form
+    except ValueError:
+        pass
+    try:                                        # HTTP-date form
+        when = parsedate_to_datetime(raw)
+    except (TypeError, ValueError):
+        return None
+    if when is None:
+        return None
+    if when.tzinfo is None:
+        when = when.replace(tzinfo=UTC)
+    return max(0.0, (when - datetime.now(UTC)).total_seconds())
+
+
+# A shared session pools the keep-alive connection across the per-post sweep
+# calls, and retries CONNECT failures only (connect=2, short backoff) — smoothing
+# the instant a reverse proxy reloads. Status codes are deliberately NOT retried
+# (status=0, raise_on_status=False): translate() maps 429/5xx → InterpreterUnavailable
+# itself, and letting urllib3 retry a draining 503 would defeat the Retry-After
+# backoff we honour upstream.
+_retry = Retry(
+    total=None, connect=2, read=0, redirect=0, status=0,
+    backoff_factor=0.3, raise_on_status=False,
+)
+session = requests.Session()
+_adapter = HTTPAdapter(max_retries=_retry)
+session.mount("http://", _adapter)
+session.mount("https://", _adapter)
+
+
+def health(base_url: str, *, timeout: float = 5.0) -> bool:
+    """True iff the Interpreter LLM engine is up. Any error (unset URL, network,
+    non-200, engine down) → False, so the sweep just no-ops rather than raising."""
+    if not base_url:
+        return False
+    try:
+        r = session.get(_url(base_url, "/v1/health"), timeout=timeout)
+    except requests.RequestException:
+        return False
+    if r.status_code != 200:
+        return False
+    engines = (r.json() or {}).get("engines") or {}
+    return bool(engines.get("llm"))
+
+
+def translate(
+    texts: list[str], *, base_url: str, target: str = "en",
+    source: str = "auto", timeout: float = 120.0,
+) -> dict:
+    """Translate a batch. Returns::
+
+        {"translations": [str, ...],        # SAME order & length as `texts`
+         "detected_lang": str | None,       # aggregate: describes the FIRST item
+         "detected_confidence": float | None,  # detector's confidence, if given
+         "engine": str | None,
+         "engine_version": str | None}
+
+    Interpreter batch metadata is aggregate (first item only) — fine for one
+    post's ``[title, description]`` batch since they share a language. Passthrough
+    items (already target-language / emoji-only) come back UNCHANGED in their
+    slot. Raises InterpreterUnavailable on a connection error / 429 / 5xx (retry
+    later, honouring Retry-After), InterpreterBadRequest on 400. (Scribe note
+    #1347.)
+    """
+    if not texts:
+        return {"translations": [], "detected_lang": None,
+                "detected_confidence": None,
+                "engine": None, "engine_version": None}
+    try:
+        r = session.post(
+            _url(base_url, "/v1/translate"),
+            json={"q": list(texts), "source": source,
+                  "target": target, "engine": "auto"},
+            timeout=timeout,
+        )
+    except requests.RequestException as e:
+        raise InterpreterUnavailable(str(e)) from e
+    if r.status_code == 400:
+        raise InterpreterBadRequest((r.json() or {}).get("error", "bad request"))
+    # A gracefully-draining service — often behind a reverse proxy — returns 429
+    # or a 5xx gateway error (502/503/504), not always a clean 503. Treat every
+    # one as "unavailable, retry later" and honour any Retry-After it sends, so a
+    # rolling Interpreter restart interrupts the sweep cleanly (instead of raising
+    # an opaque HTTPError) and resumes exactly when the service says it's ready.
+    if r.status_code == 429 or r.status_code >= 500:
+        raise InterpreterUnavailable(
+            f"interpreter unavailable (HTTP {r.status_code})",
+            retry_after=_parse_retry_after(r),
+        )
+    r.raise_for_status()
+    body = r.json() or {}
+    out = body.get("translatedText")
+    # q was an array → translatedText is an array (same order & length). Guard a
+    # scalar reply just in case (shouldn't happen for an array q).
+    if not isinstance(out, list):
+        out = [out]
+    interp = body.get("interpreter") or {}
+    detected = body.get("detectedLanguage") or {}
+    return {
+        "translations": out,
+        "detected_lang": detected.get("language"),
+        "detected_confidence": detected.get("confidence"),
+        "engine": interp.get("engine"),
+        "engine_version": interp.get("engine_version"),
+    }

backend/app/services/post_feed_service.py

@@ -200,6 +200,8 @@ class PostFeedService:
         atts_map = await self._attachments_for([post.id])
         item = self._to_dict(post, artist, source, thumbs_map, atts_map)
         item["description_full"] = html_to_plain(post.description)
+        # Full (uncapped) translated description for the detail view (#143).
+        item["description_translated_full"] = post.description_translated
         # Sanitized HTML body for faithful (semantic) rendering in the post view;
         # detail-only (the feed list stays lightweight plain text). None when the
         # post has no body. Inline `<img>` sources are remapped to locally-served
@@ -371,6 +373,12 @@ class PostFeedService:
             description_plain, truncated = None, False
         else:
             description_plain, truncated = truncate_at_word(plain_full, DESCRIPTION_LIMIT)
+        # Translation (#143): the stored translated description is already plain
+        # text; truncate it the same way for the card.
+        desc_trans = post.description_translated
+        desc_trans_short = (
+            truncate_at_word(desc_trans, DESCRIPTION_LIMIT)[0] if desc_trans else None
+        )
         thumbs_entry = thumbs_map.get(post.id, {"thumbs": [], "more": 0})
         # `source` is null for filesystem-imported posts with no live
         # subscription (alembic 0030). Frontend renders that as a
@@ -384,6 +392,11 @@ class PostFeedService:
             "downloaded_at": post.downloaded_at.isoformat(),
             "description_plain": description_plain,
             "description_truncated": truncated,
+            # Translation-forward fields (#143): shown by default when present;
+            # UI toggles back to the originals above. Source lang labels the toggle.
+            "post_title_translated": post.post_title_translated,
+            "description_translated": desc_trans_short,
+            "translated_source_lang": post.translated_source_lang,
             "artist": {"id": artist.id, "name": artist.name, "slug": artist.slug},
             "source": (
                 {"id": source.id, "platform": source.platform}

backend/app/services/provenance_service.py

@@ -29,6 +29,12 @@ def _post_dict(p: Post) -> dict:
         "date": p.post_date.isoformat() if p.post_date else None,
         "description_html": sanitize_post_html(p.description),
         "attachment_count": p.attachment_count,
+        # Translation (#143): the English title/description shown by default when
+        # a translation exists; the UI toggles to the original. Source lang labels
+        # the original.
+        "title_translated": p.post_title_translated,
+        "description_translated": p.description_translated,
+        "translated_source_lang": p.translated_source_lang,
     }
 
 

backend/app/tasks/maintenance.py

@@ -79,6 +79,14 @@ VERIFY_PAGE = 200
 FFPROBE_TIMEOUT_SECONDS = 10
 TASK_RUN_KEEP_OK_SECONDS = 24 * 3600       # 24 h
 TASK_RUN_KEEP_FAILURE_SECONDS = 7 * 24 * 3600  # 7 days
+# Orphaned staging files: downloads/imports stage into <name>.part / <name>.partial
+# then os.replace() into place (importer / external_fetch / native_ingest_common /
+# attachment_store), so a kill mid-write leaves a discardable temp, never a corrupt
+# final. cleanup_orphaned_temp_files sweeps ones left behind; the min-age guard
+# keeps it from deleting an in-flight download's staging file mid-write.
+IMAGES_ROOT = Path("/images")
+TEMP_STAGING_SUFFIXES = (".part", ".partial")
+ORPHAN_TEMP_MIN_AGE_HOURS = 6
 
 # Audit 2026-06-02: per-entity recovery sweep thresholds. Each must be
 # > the entity's longest legitimate runtime (its task's time_limit + a
@@ -339,6 +347,34 @@ def cleanup_old_tasks() -> int:
         return result.rowcount or 0
 
 
+@celery.task(name="backend.app.tasks.maintenance.cleanup_orphaned_temp_files")
+def cleanup_orphaned_temp_files() -> int:
+    """Delete orphaned .part/.partial staging files under the images root, left by
+    a download/import killed mid-write. Only removes files older than
+    ORPHAN_TEMP_MIN_AGE_HOURS so an in-flight download's staging file is never
+    pulled out from under it. Returns the count removed."""
+    if not IMAGES_ROOT.is_dir():
+        return 0
+    cutoff = datetime.now(UTC).timestamp() - ORPHAN_TEMP_MIN_AGE_HOURS * 3600
+    removed = 0
+    for path in IMAGES_ROOT.rglob("*"):
+        if path.suffix not in TEMP_STAGING_SUFFIXES or not path.is_file():
+            continue
+        try:
+            if path.stat().st_mtime >= cutoff:
+                continue          # too fresh — may be an active download
+            path.unlink()
+            removed += 1
+        except OSError as exc:
+            log.warning("cleanup_orphaned_temp_files: %s: %s", path, exc)
+    if removed:
+        log.info(
+            "cleanup_orphaned_temp_files: removed %d orphaned staging file(s)",
+            removed,
+        )
+    return removed
+
+
 @celery.task(name="backend.app.tasks.maintenance.recover_stalled_task_runs")
 def recover_stalled_task_runs() -> int:
     """Flip task_run rows stuck in 'running' past their queue-specific

backend/app/tasks/translation.py

@@ -0,0 +1,310 @@
+"""Post-text translation Celery tasks (milestone 143 + re-translate m146).
+
+Backfills non-English post title/description to the target language via the
+self-hosted Interpreter LAN service, storing the result + engine_version so
+viewing is instant and re-runs are cache-fast. Sync (Celery workers are sync),
+same pattern as the other backfill sweeps. No-op unless translation is enabled,
+a base URL is set, and the service is healthy.
+
+Two entry points:
+- ``translate_posts`` — the periodic untranslated sweep (every 8h;
+  translated_source_lang IS NULL only), one bounded chunk per fire. The Settings
+  "Translate now" button calls it with ``drain=True`` to chase the tail
+  run-until-done and clear the whole backlog in a single press.
+- ``retranslate_posts`` — after a model change, resets the stored translation
+  columns for a scoped set of posts (all, or a given set of artists) so the
+  untranslated selection re-runs them, then chases the tail until drained
+  (run-until-done). The Interpreter cache keys on engine_version: a changed
+  model genuinely re-translates, an unchanged one is ~1ms cache-fast.
+"""
+import logging
+from datetime import UTC, datetime
+
+from celery.exceptions import SoftTimeLimitExceeded
+from sqlalchemy import func, or_, select, update
+
+from ..celery_app import celery
+from ..models import ImportSettings, Post
+from ..services import interpreter_client as ic
+from ..utils.text import html_to_plain
+from ._sync_engine import sync_session_factory as _sync_session_factory
+
+log = logging.getLogger(__name__)
+
+# Bound one run's work so it commits progress rather than dying at the time
+# limit; the rest resumes next cycle (idempotent — only untranslated posts are
+# picked, so an interrupted run just re-runs = rule-89 recovery).
+_MAX_POSTS_PER_RUN = 300
+# Short gap between run-until-done chunks so a big re-translate finishes on its
+# own without monopolising the maintenance_long worker in one uninterrupted run.
+_RETRANSLATE_COUNTDOWN = 5
+# When Interpreter drains mid-chunk (graceful restart), resume the bulk
+# re-translate after the service's Retry-After hint if it sent one, else this
+# default; capped so a bogus/huge hint can't park the work longer than the daily
+# beat's own safety net would.
+_INTERRUPT_BACKOFF = 60
+_INTERRUPT_BACKOFF_MAX = 900
+
+
+def _interrupt_backoff(retry_after) -> int:
+    """Seconds to wait before resuming after an Interpreter interruption: the
+    server's Retry-After hint (capped), else the default."""
+    if retry_after and retry_after > 0:
+        return int(min(retry_after, _INTERRUPT_BACKOFF_MAX))
+    return _INTERRUPT_BACKOFF
+
+
+@celery.task(
+    name="backend.app.tasks.translation.translate_posts",
+    soft_time_limit=1800, time_limit=2100,
+)
+def translate_posts(drain: bool = False) -> str:
+    """Translate untranslated non-English post title/description (default target
+    en) via Interpreter. Per-post [title, description] batch → per-post detected
+    language. Passthrough / already-target posts are marked handled (source ==
+    target) with no stored translation. 503 or a connection error interrupts the
+    run (retry next cycle); 400 stops it (fix config); posts done so far stay
+    committed. No-op unless configured + healthy. Returns a summary string.
+
+    ``drain`` (the Settings "Translate now" button) chases the tail
+    run-until-done: on a clean chunk with work still remaining it re-enqueues
+    itself until the untranslated backlog is zero, like ``retranslate_posts``. The
+    periodic beat leaves it False → one bounded chunk per fire (the 8h cadence
+    drives the rest, enough for the trickle of newly-imported posts)."""
+    SessionLocal = _sync_session_factory()
+    with SessionLocal() as session:
+        ready = _translation_config(session)
+        if isinstance(ready, str):
+            return ready
+        base_url, target = ready
+        posts = _select_untranslated(session, None, _MAX_POSTS_PER_RUN)
+        status, translated, retry_after = _translate_batch(
+            session, posts, base_url, target,
+        )
+        # Drain mode (manual "Translate now"): chase the tail until the backlog is
+        # zero, so one press clears the whole pile instead of one 300-chunk.
+        # Termination is guaranteed — every handled post leaves the untranslated
+        # set, so the remaining count strictly decreases each chunk.
+        if status == "ok" and drain:
+            remaining = _count_untranslated(session, None)
+            if remaining:
+                translate_posts.apply_async(
+                    (), {"drain": True}, countdown=_RETRANSLATE_COUNTDOWN,
+                )
+                log.info(
+                    "translate_posts: draining — %d remaining → re-enqueued",
+                    remaining,
+                )
+        # Interpreter drained mid-chunk (graceful restart): don't make a manual
+        # "Translate now" wait a whole beat cycle — re-enqueue after its
+        # Retry-After hint (or the default backoff), preserving `drain` so a bulk
+        # drain resumes cleanly. Self-terminating: once the service is down the
+        # health gate returns "interpreter unavailable" early.
+        elif status == "interrupted" and _count_untranslated(session, None):
+            delay = _interrupt_backoff(retry_after)
+            translate_posts.apply_async((), {"drain": drain}, countdown=delay)
+            log.info(
+                "translate_posts: interrupted (service draining) → retry in %ss",
+                delay,
+            )
+    return _summary(status, translated, len(posts))
+
+
+@celery.task(
+    name="backend.app.tasks.translation.retranslate_posts",
+    soft_time_limit=1800, time_limit=2100,
+)
+def retranslate_posts(artist_ids=None, _reset_done=False) -> str:
+    """Re-translate posts after a model change. On the first call resets the
+    stored translation columns to NULL for the scoped posts — all artists when
+    ``artist_ids`` is falsy, else ``WHERE artist_id IN artist_ids`` — so the
+    normal untranslated selection re-runs them through Interpreter. Then handles
+    one bounded chunk and re-enqueues itself until the scoped backlog is drained
+    (run-until-done; ``_reset_done`` guards against wiping fresh work on the
+    follow-up chunks). No reset happens unless the service is configured +
+    healthy, so translations are never cleared when they can't be rebuilt."""
+    SessionLocal = _sync_session_factory()
+    with SessionLocal() as session:
+        ready = _translation_config(session)
+        if isinstance(ready, str):
+            return ready
+        base_url, target = ready
+
+        if not _reset_done:
+            n = _reset_translations(session, artist_ids)
+            log.info(
+                "retranslate_posts: reset %d post(s) (artist_ids=%s)",
+                n, artist_ids,
+            )
+
+        posts = _select_untranslated(session, artist_ids, _MAX_POSTS_PER_RUN)
+        status, translated, retry_after = _translate_batch(
+            session, posts, base_url, target,
+        )
+
+        # run-until-done: chase the tail when the chunk finished cleanly.
+        # Termination is guaranteed: every handled post leaves the NULL set, so
+        # the remaining count strictly decreases each chunk.
+        if status == "ok":
+            remaining = _count_untranslated(session, artist_ids)
+            if remaining:
+                retranslate_posts.apply_async(
+                    (),
+                    {"artist_ids": artist_ids, "_reset_done": True},
+                    countdown=_RETRANSLATE_COUNTDOWN,
+                )
+                log.info(
+                    "retranslate_posts: %d remaining → re-enqueued", remaining,
+                )
+        # Interpreter drained mid-chunk (graceful restart / 429 / 5xx): don't
+        # stall the bulk re-translate until the daily beat — resume it after the
+        # service's Retry-After hint (or the default backoff), with
+        # _reset_done=True so the fresh work is never re-wiped. Self-terminating:
+        # if the service is still down next run, _translation_config's health gate
+        # returns "interpreter unavailable" early and nothing re-enqueues.
+        elif status == "interrupted" and _count_untranslated(session, artist_ids):
+            delay = _interrupt_backoff(retry_after)
+            retranslate_posts.apply_async(
+                (),
+                {"artist_ids": artist_ids, "_reset_done": True},
+                countdown=delay,
+            )
+            log.info(
+                "retranslate_posts: interrupted (service draining) → retry in %ss",
+                delay,
+            )
+    return _summary(status, translated, len(posts))
+
+
+def _translation_config(session):
+    """Resolve (base_url, target) if translation is enabled + healthy, else a
+    short status string ("disabled" / "interpreter unavailable") for the caller
+    to return. Centralises the guard so translate/retranslate agree exactly."""
+    cfg = ImportSettings.load_sync(session)
+    if not cfg.translation_enabled or not cfg.interpreter_base_url.strip():
+        return "disabled"
+    base_url = cfg.interpreter_base_url.strip()
+    target = (cfg.translation_target_lang or "en").strip() or "en"
+    if not ic.health(base_url):
+        return "interpreter unavailable"
+    return base_url, target
+
+
+def _untranslated_filter(stmt, artist_ids):
+    """Add the untranslated-post predicate (+ optional artist scope) to a
+    select/count over Post. Untranslated = translated_source_lang IS NULL with
+    some text to translate."""
+    stmt = stmt.where(
+        Post.translated_source_lang.is_(None)
+    ).where(or_(
+        Post.post_title.is_not(None), Post.description.is_not(None),
+    ))
+    if artist_ids:
+        stmt = stmt.where(Post.artist_id.in_(artist_ids))
+    return stmt
+
+
+def _select_untranslated(session, artist_ids, limit):
+    return session.execute(
+        _untranslated_filter(select(Post), artist_ids).limit(limit)
+    ).scalars().all()
+
+
+def _count_untranslated(session, artist_ids) -> int:
+    return int(session.execute(
+        _untranslated_filter(select(func.count(Post.id)), artist_ids)
+    ).scalar_one())
+
+
+def _reset_translations(session, artist_ids) -> int:
+    """Clear the stored translation columns for scoped, already-handled posts so
+    the untranslated sweep re-runs them. Only touches rows that were translated
+    (translated_source_lang IS NOT NULL) — untranslated rows are already NULL.
+    Returns the row count reset (commits it)."""
+    stmt = (
+        update(Post)
+        .where(Post.translated_source_lang.is_not(None))
+        .values(
+            post_title_translated=None,
+            description_translated=None,
+            translated_source_lang=None,
+            translation_engine_version=None,
+            translated_at=None,
+        )
+    )
+    if artist_ids:
+        stmt = stmt.where(Post.artist_id.in_(artist_ids))
+    n = session.execute(stmt).rowcount
+    session.commit()
+    return n
+
+
+def _translate_batch(session, posts, base_url: str, target: str):
+    """Translate each post in the chunk with a per-post commit (an interrupted
+    run keeps progress). Returns (status, translated, retry_after) where status is
+    one of "ok" / "interrupted" (unavailable/drain) / "stopped" (400) / "timeout";
+    retry_after is the server's Retry-After hint in seconds on an interrupt, else
+    None."""
+    translated = 0
+    for post in posts:
+        try:
+            translated += _translate_one(session, post, base_url, target)
+            session.commit()
+        except ic.InterpreterUnavailable as e:
+            session.rollback()
+            return "interrupted", translated, getattr(e, "retry_after", None)
+        except ic.InterpreterBadRequest as e:
+            session.rollback()
+            log.warning("translate bad request: %s", e)
+            return "stopped", translated, None
+        except SoftTimeLimitExceeded:
+            return "timeout", translated, None
+    return "ok", translated, None
+
+
+def _summary(status: str, translated: int, scanned: int) -> str:
+    if status == "interrupted":
+        return f"interrupted (service down) — translated={translated}"
+    if status == "stopped":
+        return f"stopped (bad request) — translated={translated}"
+    if status == "timeout":
+        return f"time limit — translated={translated}"
+    return f"translated={translated} scanned={scanned}"
+
+
+def _translate_field(text: str, base_url: str, target: str):
+    """Translate ONE field independently. Returns (translated, source_lang,
+    engine_version), or (None, None, None) when there's nothing to store — empty
+    text, already the target language, or a passthrough (engine "none"). Per-field
+    (not aggregate first-item) detection so a non-English description still gets
+    translated when the title is already English (mixed-language posts)."""
+    if not text:
+        return None, None, None
+    res = ic.translate([text], base_url=base_url, target=target)
+    detected = res["detected_lang"] or target
+    if detected == target or res["engine"] == "none":
+        return None, None, None
+    return res["translations"][0], detected, res["engine_version"]
+
+
+def _translate_one(session, post, base_url: str, target: str) -> int:
+    """Translate a post's title/description in place, each field independently.
+    Returns 1 if it stored at least one translation, 0 when the post is all
+    passthrough/empty (still marks it handled so the sweep won't revisit it)."""
+    title = (post.post_title or "").strip()
+    desc = (html_to_plain(post.description) if post.description else "") or ""
+    desc = desc.strip()
+    title_tr, title_lang, title_ev = _translate_field(title, base_url, target)
+    desc_tr, desc_lang, desc_ev = _translate_field(desc, base_url, target)
+    if title_tr is None and desc_tr is None:
+        # Nothing non-target (or nothing to translate) → handled, store nothing.
+        post.translated_source_lang = target
+        return 0
+    post.post_title_translated = title_tr
+    post.description_translated = desc_tr
+    # Source lang = whichever field was actually non-target (for a mixed post,
+    # the translated field's language, not the already-English one).
+    post.translated_source_lang = title_lang or desc_lang
+    post.translation_engine_version = title_ev or desc_ev
+    post.translated_at = datetime.now(UTC)
+    return 1

docker-compose.yml

@@ -8,6 +8,35 @@
 # run `docker compose up` from this directory and switches images to
 # local builds + DEBUG logging.
 
+# Rolling-deploy safety (Swarm / `docker stack deploy`): update one task at a
+# time, START the new task before stopping the old (zero-downtime via the ingress
+# mesh), and if the new task doesn't reach a healthy state within `monitor`, roll
+# back to the previous image automatically. `monitor` is sized above web's
+# healthcheck start_period so a broken image that never goes healthy is caught.
+# Plain `docker compose up` ignores `deploy:` (it warns + skips), so the dev
+# override is unaffected. Referenced by each long-lived service below.
+x-deploy-policy: &deploy_policy
+  update_config:
+    order: start-first
+    failure_action: rollback
+    monitor: 90s
+  rollback_config:
+    order: start-first
+  restart_policy:
+    condition: any
+    delay: 10s
+
+# Worker liveness: ping THIS container's celery node over the broker. Lenient
+# (60s interval, 3 retries, 60s start_period) so a transient broker blip never
+# false-flags a worker into a rollback. `$$HOSTNAME` → `$HOSTNAME` for the shell;
+# celery's default node name is celery@<hostname> (the container id).
+x-celery-healthcheck: &celery_healthcheck
+  test: ["CMD-SHELL", "celery -A backend.app.celery_app:celery inspect ping -d celery@$$HOSTNAME --timeout 10 >/dev/null 2>&1"]
+  interval: 60s
+  timeout: 15s
+  retries: 3
+  start_period: 60s
+
 services:
   redis:
     image: redis:7-alpine
@@ -47,6 +76,24 @@ services:
   web:
     image: git.fabledsword.com/bvandeusen/fabledcurator:dev
     command: ["web"]
+    # Graceful shutdown: give the container time to drain in-flight work on a
+    # deploy (docker SIGTERMs, then SIGKILLs after this window — default is only
+    # 10s, far too short for real jobs). Hypercorn/Celery both warm-shut-down on
+    # SIGTERM; per-lane values sized to typical task length. Anything that still
+    # outruns the window is re-queued (task_reject_on_worker_lost) and re-driven
+    # by the 5-min recovery sweeps, so a kill never corrupts. web = short HTTP
+    # requests + the occasional file download.
+    stop_grace_period: 30s
+    # Liveness for rolling deploys: /api/health is a no-DB 200 (just proves the
+    # app booted + serves HTTP after `alembic upgrade head`). start_period covers
+    # the migration + boot so a slow start isn't mis-flagged.
+    healthcheck:
+      test: ["CMD-SHELL", "python -c \"import urllib.request,sys; sys.exit(0 if urllib.request.urlopen('http://localhost:8080/api/health', timeout=5).status==200 else 1)\""]
+      interval: 15s
+      timeout: 6s
+      retries: 3
+      start_period: 40s
+    deploy: *deploy_policy
     ports:
       - "${PORT:-8080}:8080"
     environment: &app_env
@@ -77,6 +124,10 @@ services:
   worker:
     image: git.fabledsword.com/bvandeusen/fabledcurator:dev
     command: ["worker"]
+    # Drain in-flight import/thumbnail/download tasks before SIGKILL on deploy.
+    stop_grace_period: 90s
+    healthcheck: *celery_healthcheck
+    deploy: *deploy_policy
     environment:
       <<: *app_env
       CELERY_QUEUES: default,import,thumbnail,download
@@ -93,6 +144,10 @@ services:
   scheduler:
     image: git.fabledsword.com/bvandeusen/fabledcurator:dev
     command: ["scheduler"]
+    # Quick maintenance/scan lane + beat — short tasks, modest drain window.
+    stop_grace_period: 60s
+    healthcheck: *celery_healthcheck
+    deploy: *deploy_policy
     environment:
       <<: *app_env
       CELERY_QUEUES: maintenance,scan
@@ -110,6 +165,12 @@ services:
   maintenance-long:
     image: git.fabledsword.com/bvandeusen/fabledcurator:dev
     command: ["worker"]
+    # Longest lane (DB backups, library audits, translation backfill) — give it
+    # the most room to finish a chunk gracefully. Chunked + idempotent, so a job
+    # that still outruns this resumes cleanly next run rather than corrupting.
+    stop_grace_period: 180s
+    healthcheck: *celery_healthcheck
+    deploy: *deploy_policy
     environment:
       <<: *app_env
       CELERY_QUEUES: maintenance_long
@@ -125,6 +186,10 @@ services:
   ml-worker:
     image: git.fabledsword.com/bvandeusen/fabledcurator-ml:dev
     command: ["ml-worker"]
+    # A single GPU inference pass can run tens of seconds — let it finish.
+    stop_grace_period: 120s
+    healthcheck: *celery_healthcheck
+    deploy: *deploy_policy
     environment:
       <<: *app_env
     volumes:

frontend/src/components/artist/ArtistManagementTab.vue

@@ -101,6 +101,47 @@
       </v-card>
     </v-dialog>
 
+    <section class="fc-artist-mgmt__sec">
+      <h2 class="fc-h2">Translation</h2>
+      <p class="fc-muted text-body-2 mb-3">
+        Re-translate every post by {{ overview.name }} through the current
+        Interpreter model — clears the stored translations and rebuilds them.
+        Use this after switching translation models to refresh just this artist.
+      </p>
+      <div class="d-flex align-center flex-wrap" style="gap: 10px;">
+        <v-btn
+          size="small" variant="tonal" rounded="pill"
+          prepend-icon="mdi-translate"
+          :loading="retranslating" :disabled="!translationEnabled"
+          @click="confirmRetranslate = true"
+        >Re-translate posts</v-btn>
+        <span v-if="!translationEnabled" class="fc-muted text-caption">
+          Translation is off — enable it in Settings → Maintenance.
+        </span>
+      </div>
+    </section>
+
+    <!-- m146: per-artist re-translate — clears + rebuilds this artist's stored
+         translations (used after a translation-model change). -->
+    <v-dialog v-model="confirmRetranslate" max-width="440">
+      <v-card>
+        <v-card-title class="fc-h2">Re-translate {{ overview.name }}?</v-card-title>
+        <v-card-text class="text-body-2">
+          Clears the stored translation for every post by
+          <strong>{{ overview.name }}</strong> and re-runs them through your
+          current Interpreter model. Unchanged text comes back from the cache
+          instantly. Runs in the background until done.
+        </v-card-text>
+        <v-card-actions>
+          <v-spacer />
+          <v-btn variant="text" @click="confirmRetranslate = false">Cancel</v-btn>
+          <v-btn color="accent" :loading="retranslating" @click="onRetranslate">
+            Re-translate
+          </v-btn>
+        </v-card-actions>
+      </v-card>
+    </v-dialog>
+
     <section class="fc-artist-mgmt__sec">
       <h2 class="fc-h2">Danger zone</h2>
       <ArtistDangerZone
@@ -113,9 +154,11 @@
 </template>
 
 <script setup>
-import { computed, ref } from 'vue'
+import { computed, onMounted, ref } from 'vue'
 import { useRouter, RouterLink } from 'vue-router'
 
+import { useApi } from '../../composables/useApi.js'
+import { useImportStore } from '../../stores/import.js'
 import { useSourcesStore } from '../../stores/sources.js'
 import { toast } from '../../utils/toast.js'
 import ArtistDangerZone from './ArtistDangerZone.vue'
@@ -125,8 +168,38 @@ const props = defineProps({
 })
 
 const router = useRouter()
+const api = useApi()
+const importStore = useImportStore()
 const sources = useSourcesStore()
 
+// m146: per-artist re-translate. Gated on translation being enabled globally
+// (the endpoint 400s otherwise) — read the shared import settings once.
+const translationEnabled = ref(false)
+const retranslating = ref(false)
+const confirmRetranslate = ref(false)
+
+onMounted(async () => {
+  try {
+    await importStore.loadSettings()
+    translationEnabled.value = !!importStore.settings?.translation_enabled
+  } catch { /* non-fatal — the button just stays disabled */ }
+})
+
+async function onRetranslate () {
+  retranslating.value = true
+  try {
+    await api.post('/api/settings/translation/retranslate', {
+      body: { artist_id: props.overview.id },
+    })
+    confirmRetranslate.value = false
+    toast({ text: `Re-translating ${props.overview.name}…`, type: 'success' })
+  } catch (e) {
+    toast({ text: `Re-translate failed: ${e.message}`, type: 'error' })
+  } finally {
+    retranslating.value = false
+  }
+}
+
 // #130: move a source into another artist.
 const moveOpen = ref(false)
 const moveSource = ref(null)

frontend/src/components/modal/ProvenancePanel.vue

@@ -42,13 +42,23 @@
             · {{ e.post.attachment_count }} files
           </span>
         </div>
+        <div v-if="hasTranslation(e)" class="fc-prov__actions">
+          <a
+            href="#" @click.prevent="toggleOrig(e.provenance_id)"
+          >{{ showOrig[e.provenance_id] ? 'Show translation' : `Show original${langLabel(e)}` }}</a>
+        </div>
         <div v-if="e.post.description_html" class="fc-prov__actions">
           <a
             href="#" @click.prevent="toggleDesc(e.provenance_id)"
           >{{ expanded[e.provenance_id] ? 'Hide description ▴' : 'Show description ▾' }}</a>
         </div>
+        <!-- Translated body = plain text; original = sanitized HTML (#143). -->
+        <p
+          v-if="showTranslated(e) && expanded[e.provenance_id] && e.post.description_translated"
+          class="fc-prov__desc"
+        >{{ e.post.description_translated }}</p>
         <div
-          v-if="e.post.description_html && expanded[e.provenance_id]"
+          v-else-if="e.post.description_html && expanded[e.provenance_id]"
           class="fc-prov__desc" v-html="e.post.description_html"
         />
       </article>
@@ -117,8 +127,12 @@ const effectiveImage = computed(() => props.image ?? modal.current)
 // 2026-05-28. Reset when the viewed image changes.
 const expanded = reactive({})
 function toggleDesc(id) { expanded[id] = !expanded[id] }
+// Per-entry "show the original (untranslated) text" toggle (#143).
+const showOrig = reactive({})
+function toggleOrig(id) { showOrig[id] = !showOrig[id] }
 watch(() => effectiveId.value, () => {
   for (const k of Object.keys(expanded)) delete expanded[k]
+  for (const k of Object.keys(showOrig)) delete showOrig[k]
 })
 
 watch(
@@ -157,10 +171,23 @@ const show = computed(() => {
 const attachments = computed(() => state.value?.attachments || [])
 
 function postDate(e) { return formatPostDate(e.post.date) }
+// Translation-forward (#143): show the English by default when present.
+function hasTranslation(e) {
+  return !!(e.post.title_translated || e.post.description_translated)
+}
+function showTranslated(e) {
+  return hasTranslation(e) && !showOrig[e.provenance_id]
+}
+function langLabel(e) {
+  return e.post.translated_source_lang ? ` (${e.post.translated_source_lang})` : ''
+}
 function postTitle(e) {
   // Titles can arrive as stored HTML (e.g. "<strong>…</strong>"); render
   // as plain text (the CSS makes it bold).
-  return toPlainText(e.post.title) || `Post ${e.post.external_post_id}`
+  const t = showTranslated(e) && e.post.title_translated
+    ? e.post.title_translated
+    : e.post.title
+  return toPlainText(t) || `Post ${e.post.external_post_id}`
 }
 
 function openPost(postId, artistId) {

frontend/src/components/modal/TagChip.vue

@@ -1,7 +1,7 @@
 <template>
   <span class="fc-tag-chip" @mouseenter="onEnter" @mouseleave="onLeave">
     <v-chip
-      size="small" closable
+      size="default" :closable="!unconfirmedAuto"
       :color="store.colorFor(tag.kind)" variant="tonal"
       class="fc-tag-chip__nav"
       role="link"
@@ -9,27 +9,33 @@
       @click="$emit('navigate', tag)"
       @click:close="$emit('remove', tag.id)"
     >
-      <v-icon start size="x-small">{{ iconFor(tag.kind) }}</v-icon>
+      <v-icon start size="small">{{ iconFor(tag.kind) }}</v-icon>
       <span class="fc-tag-chip__name">{{ tag.name }}</span><v-icon
         v-if="tag.is_system" end size="x-small" class="fc-tag-chip__system"
         title="System tag — tagged items are excluded from training other concepts"
       >mdi-shield-outline</v-icon><span
         v-if="tag.fandom_id" class="fc-tag-chip__fandom"
         :title="tag.fandom_name ? `Fandom: ${tag.fandom_name}` : 'Has a fandom'"
-      >→<template v-if="fandomLabel">&nbsp;{{ fandomLabel }}</template></span><span
-        v-if="unconfirmedAuto" class="fc-tag-chip__auto"
-        title="Auto-applied — provisional: it won't train the model and can be retracted until you confirm it."
-      >auto</span>
+      >→<template v-if="fandomLabel">&nbsp;{{ fandomLabel }}</template></span>
+      <!-- Provisional auto-tag: an in-pill yes/no pair REPLACES the ✕ (the pair
+           itself signals "auto" — no separate label, operator 2026-07-07). Yes
+           confirms it (trains + shields from retraction); No removes it (records
+           a negative). Both hand focus back to the tag input via TagPanel. -->
+      <span v-if="unconfirmedAuto" class="fc-tag-chip__verdict">
+        <button
+          type="button" class="fc-tag-chip__yes"
+          :title="`Yes — keep “${tag.name}” (trains the model, won't be retracted)`"
+          :aria-label="`Confirm ${tag.name}`"
+          @click.stop="$emit('confirm', tag)"
+        ><v-icon size="15">mdi-check</v-icon></button>
+        <button
+          type="button" class="fc-tag-chip__no"
+          :title="`No — remove “${tag.name}”`"
+          :aria-label="`Reject ${tag.name}`"
+          @click.stop="$emit('remove', tag.id)"
+        ><v-icon size="15">mdi-close</v-icon></button>
+      </span>
     </v-chip>
-    <!-- Keep/confirm an auto-applied tag: promotes it to a training positive and
-         shields it from the retraction sweep (milestone 139). Only shown for
-         provisional (unconfirmed) auto-tags. -->
-    <button
-      v-if="unconfirmedAuto" class="fc-tag-chip__confirm" type="button"
-      :title="`Keep “${tag.name}” — confirm this auto-tag so it trains the model and won't be retracted`"
-      :aria-label="`Confirm ${tag.name}`"
-      @click.stop="$emit('confirm', tag)"
-    ><v-icon size="16">mdi-check</v-icon></button>
     <!-- Modal-safe kebab is baked into KebabMenu (this chip lives in the
          teleported image modal — #711). System tags hide it entirely: rename
          is refused server-side (the hygiene machinery keys on the row) and
@@ -71,8 +77,8 @@ const store = useTagStore()
 const api = useApi()
 
 // An auto-applied tag the operator hasn't confirmed yet — provisional (milestone
-// 139): it doesn't train the model and the retraction sweep can drop it. Shows
-// the "auto" badge + a Keep/confirm button. `source`/`confirmed` come from the
+// 139): it doesn't train the model and the retraction sweep can drop it. Shows an
+// in-pill yes/no pair in place of the ✕. `source`/`confirmed` come from the
 // applied-tags payload (list_for_image / get_image_with_tags).
 const unconfirmedAuto = computed(() =>
   AUTO_SOURCES.includes(props.tag.source) && !props.tag.confirmed
@@ -130,13 +136,26 @@ function iconFor (k) { return KIND_ICONS[k] || 'mdi-tag' }
 </script>
 
 <style scoped>
-/* A chip must never exceed the rail — a long character+fandom(+AUTO) chip used
-   to overflow the right edge and clip its close ✕ (operator-flagged 2026-07-06).
-   The name is the elastic part: it ellipsis-truncates so the ✕, fandom, and AUTO
-   badge stay reachable. Full name is still available via the chip's hover title. */
+/* A chip must never exceed the rail — a long character+fandom chip used to
+   overflow the right edge and clip its trailing control (operator-flagged
+   2026-07-06). The name is the elastic part: it ellipsis-truncates so the ✕ (or
+   the auto-tag yes/no pair) and fandom stay reachable. Full name is on the
+   chip's hover title. */
 .fc-tag-chip { display: inline-flex; align-items: center; gap: 1px; max-width: 100%; min-width: 0; }
 .fc-tag-chip__nav { max-width: 100%; min-width: 0; }
+/* Tonal chips (esp. character = info) wash out against the dark rail — the fill
+   is intentionally faint. Give every tag chip a thin border in its OWN kind
+   colour (currentColor = the tonal chip's themed foreground) so the edge reads
+   clearly without touching the fill (operator-asked 2026-07-08). Theme-aware:
+   currentColor tracks the kind colour in either light or dark. */
+.fc-tag-chip__nav { border: thin solid color-mix(in srgb, currentColor 55%, transparent); }
 .fc-tag-chip__nav :deep(.v-chip__content) { min-width: 0; overflow: hidden; }
+/* The bigger size=default chip widens Vuetify's negative start-margin on the
+   leading kind-icon, pulling it LEFT of the content box above — where that
+   overflow:hidden then clips the icon's left edge as a vertical slice
+   (operator-flagged 2026-07-08). Zero the pull so the icon sits inside the clip
+   box; the chip's own 12px padding keeps a comfortable left inset. */
+.fc-tag-chip__nav :deep(.v-icon--start) { margin-inline-start: 0; }
 .fc-tag-chip__name {
   overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
   min-width: 0; flex: 0 1 auto;
@@ -152,28 +171,27 @@ function iconFor (k) { return KIND_ICONS[k] || 'mdi-tag' }
 .fc-tag-chip__kebab { opacity: 0.7; }
 .fc-tag-chip:hover .fc-tag-chip__kebab { opacity: 1; }
 .fc-tag-chip__fandom { opacity: 0.7; font-size: 0.85em; }
-/* "auto" = provisional (auto-applied, unconfirmed). Quiet pill inside the chip. */
-.fc-tag-chip__auto {
-  display: inline-block; vertical-align: middle; margin-left: 4px;
-  font-size: 9px; font-weight: 700;
-  text-transform: uppercase; letter-spacing: 0.04em;
-  color: rgb(var(--v-theme-on-surface-variant));
-  background: rgb(var(--v-theme-surface-light));
-  border: 1px solid rgb(var(--v-theme-on-surface-variant), 0.3);
-  padding: 0 4px; border-radius: 999px;
+/* Provisional auto-tag: a green ✓ / red ✗ pair in place of the ✕. The yes/no is
+   obvious enough on its own, so there's no "auto" label (operator-asked
+   2026-07-07). flex:0 0 auto keeps it visible while the name ellipsis-truncates. */
+.fc-tag-chip__verdict {
+  flex: 0 0 auto; display: inline-flex; align-items: center; gap: 3px;
+  margin-left: 5px;
 }
-/* Keep/confirm — the SAME filled green ✓ circle as the suggestion accept button
-   (.fc-act--yes in SuggestionItem), so "accept this tag" reads identically
-   wherever it appears (operator-asked 2026-07-06). */
-.fc-tag-chip__confirm {
-  flex: 0 0 auto;
-  width: 26px; height: 26px; border-radius: 50%; border: none; cursor: pointer;
+/* Solid-filled (white glyph on a full success/error circle) so accept/reject
+   stay well-defined even on a muted tonal chip — e.g. character (info) — instead
+   of a faint icon that only lit up on hover. Mirrors the Suggestions rail's
+   verdict buttons so the affordance reads identically (operator-asked 2026-07-08). */
+.fc-tag-chip__yes, .fc-tag-chip__no {
   display: inline-flex; align-items: center; justify-content: center;
-  color: #fff; background: rgb(var(--v-theme-success));
-  opacity: 0.9; transition: transform 0.1s, opacity 0.1s;
+  width: 22px; height: 22px; padding: 0; border: none; border-radius: 50%;
+  color: #fff; cursor: pointer; opacity: 0.92;
+  transition: transform 0.1s, opacity 0.1s;
 }
-.fc-tag-chip__confirm:hover { opacity: 1; transform: scale(1.1); }
-.fc-tag-chip__confirm:focus-visible {
-  outline: 2px solid rgb(var(--v-theme-accent)); outline-offset: 1px;
+.fc-tag-chip__yes { background: rgb(var(--v-theme-success)); }
+.fc-tag-chip__no { background: rgb(var(--v-theme-error)); }
+.fc-tag-chip__yes:hover, .fc-tag-chip__no:hover { opacity: 1; transform: scale(1.1); }
+.fc-tag-chip__yes:focus-visible, .fc-tag-chip__no:focus-visible {
+  outline: 2px solid rgb(var(--v-theme-accent)); outline-offset: 2px;
 }
 </style>

frontend/src/components/modal/TagPanel.vue

@@ -116,6 +116,10 @@ async function onConfirm(tag) {
   try {
     await api.post(`/api/images/${host.currentImageId}/tags/${tag.id}/confirm`)
     await host.reloadTags()
+    // Return the cursor to the tag input — its resting position in these views,
+    // matching every other chip action (remove/accept) so the keyboard flow
+    // never leaves the field (operator-asked 2026-07-07).
+    focusTagInput()
   }
   catch (e) { errorMsg.value = e.message }
 }

frontend/src/components/posts/PostCard.vue

@@ -58,16 +58,23 @@
       </div>
 
       <div class="fc-post-card__text">
-        <h3 v-if="plainTitle" class="fc-post-card__title">{{ plainTitle }}</h3>
+        <h3 v-if="displayTitle" class="fc-post-card__title">{{ displayTitle }}</h3>
         <h3 v-else class="fc-post-card__title fc-post-card__title--missing">
           Post {{ post.external_post_id }}
         </h3>
+        <!-- Translation toggle (#143): English shown by default; reveal the
+             original, labelled with its detected language. -->
+        <button
+          v-if="hasTranslation" type="button" class="fc-post-card__lang"
+          :title="showOriginal ? 'Show the English translation' : `Show the original${sourceLangLabel} text`"
+          @click.stop="showOriginal = !showOriginal"
+        >{{ showOriginal ? 'Show translation' : `Show original${sourceLangLabel}` }}</button>
 
         <!-- Faithful (semantic) body render once expanded: backend-sanitized
              HTML (headings, lists, links, inline images). Collapsed and the
              no-detail fallback stay plain text. -->
         <div
-          v-if="hasDescription && descExpanded && descHtml"
+          v-if="hasDescription && showHtmlBody"
           class="fc-post-card__desc fc-post-card__desc--html"
           v-html="descHtml"
         />
@@ -75,7 +82,7 @@
           v-else-if="hasDescription" ref="descEl"
           class="fc-post-card__desc"
           :class="{ 'fc-post-card__desc--clamped': !descExpanded }"
-        >{{ descText }}</p>
+        >{{ descTextDisplay }}</p>
         <p v-else class="fc-post-card__desc fc-post-card__desc--missing">
           (no description)
         </p>
@@ -231,6 +238,32 @@ const canExpand = computed(
   () => props.post.description_truncated === true || cssOverflow.value,
 )
 
+// --- translation-forward (#143): the English is shown by default when a
+// translation exists; a per-card toggle reveals the original. Translations are
+// plain text, so showTranslated also decides HTML-vs-plain body rendering.
+const showOriginal = ref(false)
+const hasTranslation = computed(
+  () => !!(props.post.post_title_translated || props.post.description_translated),
+)
+const showTranslated = computed(() => hasTranslation.value && !showOriginal.value)
+const sourceLangLabel = computed(() =>
+  props.post.translated_source_lang ? ` (${props.post.translated_source_lang})` : '',
+)
+const displayTitle = computed(() =>
+  showTranslated.value && props.post.post_title_translated
+    ? toPlainText(props.post.post_title_translated)
+    : plainTitle.value,
+)
+const descTextDisplay = computed(() => {
+  if (!showTranslated.value) return descText.value
+  return descExpanded.value
+    ? (detail.value?.description_translated_full || props.post.description_translated)
+    : props.post.description_translated
+})
+const showHtmlBody = computed(
+  () => !showTranslated.value && descExpanded.value && !!descHtml.value,
+)
+
 function measureOverflow () {
   const el = descEl.value
   cssOverflow.value = !!el && el.scrollHeight > el.clientHeight + 1
@@ -467,6 +500,19 @@ function formatBytes (n) {
   font-size: 0.85rem; font-weight: 600;
 }
 .fc-post-card__more:hover { text-decoration: underline; }
+/* Translation toggle (#143) — quiet secondary affordance under the title. */
+.fc-post-card__lang {
+  display: block; margin: 2px 0 6px; padding: 0;
+  background: none; border: 0; cursor: pointer;
+  color: rgb(var(--v-theme-on-surface-variant));
+  font-size: 0.75rem; font-weight: 600;
+}
+.fc-post-card__lang:hover {
+  text-decoration: underline; color: rgb(var(--v-theme-accent));
+}
+.fc-post-card__lang:focus-visible {
+  outline: 2px solid rgb(var(--v-theme-accent)); outline-offset: 1px;
+}
 
 .fc-post-card__atts {
   display: flex; flex-wrap: wrap; gap: 8px;

frontend/src/components/settings/MaintenancePanel.vue

@@ -13,6 +13,7 @@
       </p>
       <div class="fc-tile-stack">
         <ImportFiltersForm />
+        <TranslationCard />
       </div>
     </section>
 
@@ -69,6 +70,7 @@
 import { onMounted, onUnmounted } from 'vue'
 
 import ImportFiltersForm from './ImportFiltersForm.vue'
+import TranslationCard from './TranslationCard.vue'
 import MLBackfillCard from './MLBackfillCard.vue'
 import ThumbnailBackfillCard from './ThumbnailBackfillCard.vue'
 import ArchiveReextractCard from './ArchiveReextractCard.vue'

frontend/src/components/settings/TranslationCard.vue

@@ -0,0 +1,312 @@
+<template>
+  <MaintenanceTile
+    icon="mdi-translate"
+    title="Post translation (Interpreter)"
+    blurb="Translate non-English post titles + descriptions to English via your self-hosted Interpreter service, so archived posts read naturally."
+  >
+    <div class="d-flex align-center mb-3" style="gap: 10px;">
+      <span class="fc-section-h">Enabled</span>
+      <v-switch
+        v-model="enabled" :loading="busy" hide-details density="compact"
+        color="success" class="ml-auto" @update:model-value="onToggle"
+      />
+    </div>
+    <p class="fc-muted text-body-2 mb-3">
+      Point this at your Interpreter service. It stays off until a URL is set, and
+      only translates posts whose text isn't already in the target language — the
+      English is shown by default on post cards, with a toggle back to the original.
+    </p>
+
+    <v-text-field
+      v-model="baseUrl" label="Interpreter base URL"
+      placeholder="http://interpreter.your-domain/" density="compact"
+      hide-details class="mb-3" :disabled="busy" @change="onSave"
+    />
+    <v-text-field
+      v-model="targetLang" label="Target language" density="compact"
+      hide-details style="max-width: 160px;" class="mb-3" :disabled="busy"
+      @change="onSave"
+    />
+
+    <div class="d-flex align-center flex-wrap mb-3" style="gap: 8px;">
+      <v-icon size="12" :color="statusColor">mdi-circle</v-icon>
+      <span class="fc-muted text-body-2">{{ statusText }}</span>
+      <v-btn
+        size="x-small" variant="tonal" rounded="pill" class="ml-2"
+        :loading="testing" :disabled="!baseUrl" @click="onTest"
+      >Test connection</v-btn>
+      <span
+        v-if="testResult !== null" class="text-caption"
+        :class="testResult ? 'text-success' : 'text-error'"
+      >{{ testResult ? '✓ reachable' : '✗ unreachable' }}</span>
+    </div>
+
+    <div class="d-flex align-center flex-wrap" style="gap: 10px;">
+      <v-btn
+        size="small" variant="flat" color="accent" rounded="pill"
+        prepend-icon="mdi-translate" :loading="running"
+        :disabled="!enabled || !baseUrl" @click="onRun"
+      >Translate now</v-btn>
+      <v-btn
+        size="small" variant="tonal" rounded="pill"
+        prepend-icon="mdi-refresh" :loading="retranslating"
+        :disabled="!enabled || !baseUrl" @click="confirmAll = true"
+      >Re-translate all</v-btn>
+      <span
+        v-if="status && status.active"
+        class="fc-muted text-caption d-inline-flex align-center" style="gap: 6px;"
+      >
+        <v-progress-circular indeterminate size="12" width="2" color="accent" />
+        Translating… {{ status.untranslated_count }} remaining
+      </span>
+      <span v-else-if="status" class="fc-muted text-caption">
+        {{ status.untranslated_count }}
+        post{{ status.untranslated_count === 1 ? '' : 's' }} awaiting translation
+      </span>
+    </div>
+    <p
+      v-if="status && status.last_run && ['error', 'timeout'].includes(status.last_run.status)"
+      class="text-caption text-error mt-1 mb-0"
+    >
+      Last translation run ended with “{{ status.last_run.status }}”. It resumes on
+      the next sweep; check the Interpreter connection if it persists.
+    </p>
+    <p class="fc-muted text-caption mt-2 mb-0">
+      Use <strong>Re-translate all</strong> after switching the Interpreter model —
+      it clears every stored translation and re-runs it through the new model
+      (unchanged text is served from cache, so it's cheap). To refresh just one
+      artist, use the Re-translate button on that artist's page.
+    </p>
+
+    <v-divider class="my-3" />
+
+    <!-- Diagnostic probe (task #1376): paste text → what Interpreter DETECTS
+         (language + confidence) and returns, without saving. Used to see why a
+         short/abbreviation-heavy English title gets mis-detected, and to pick a
+         detection-confidence / min-length guard from real numbers. -->
+    <div class="mb-1">
+      <span class="fc-section-h">Test translation</span>
+      <p class="fc-muted text-caption mt-1 mb-2">
+        Paste a title or snippet to see what Interpreter detects and returns —
+        handy for checking why a short string is mis-detected. Nothing is saved.
+      </p>
+    </div>
+    <v-textarea
+      v-model="probeText" label="Text to test" rows="2" auto-grow
+      density="compact" hide-details class="mb-2" :disabled="!baseUrl"
+    />
+    <div class="d-flex align-center flex-wrap mb-2" style="gap: 8px;">
+      <v-btn
+        size="small" variant="tonal" rounded="pill" prepend-icon="mdi-magnify"
+        :loading="probing" :disabled="!baseUrl || !probeText.trim()"
+        @click="onProbe"
+      >Test translation</v-btn>
+    </div>
+    <v-sheet
+      v-if="probeResult" rounded class="pa-3 mb-1 text-body-2"
+      color="rgba(var(--v-theme-accent), 0.06)"
+    >
+      <div class="d-flex flex-wrap" style="gap: 4px 16px;">
+        <span>
+          <span class="fc-muted">Detected:</span>
+          <strong>{{ probeResult.detected_lang || '—' }}</strong>
+        </span>
+        <span v-if="probeResult.detected_confidence != null">
+          <span class="fc-muted">Confidence:</span>
+          <strong>{{ fmtConf(probeResult.detected_confidence) }}</strong>
+        </span>
+        <span>
+          <span class="fc-muted">Engine:</span>
+          {{ probeResult.engine || '—' }}<template
+            v-if="probeResult.engine_version"
+          > ({{ probeResult.engine_version }})</template>
+        </span>
+        <span><span class="fc-muted">Target:</span> {{ probeResult.target }}</span>
+      </div>
+      <v-divider class="my-2" />
+      <div class="fc-muted mb-1">
+        Result<template v-if="probeResult.detected_lang === probeResult.target">
+          — already {{ probeResult.target }}, so the sweep leaves it as-is</template>:
+      </div>
+      <p class="mb-0" style="white-space: pre-wrap;">{{
+        probeResult.translated || '(no change)'
+      }}</p>
+    </v-sheet>
+
+    <v-alert
+      v-if="err" type="error" variant="tonal" density="compact"
+      class="mt-3" closable @click:close="err = null"
+    >{{ err }}</v-alert>
+
+    <!-- m146: re-translate-everything is a bigger hammer than 'Translate now'
+         (it clears + rebuilds all translations), so it asks first. -->
+    <v-dialog v-model="confirmAll" max-width="440">
+      <v-card>
+        <v-card-title>Re-translate everything?</v-card-title>
+        <v-card-text class="text-body-2">
+          This clears the stored translation for <strong>every</strong> post and
+          re-runs them through your current Interpreter model. Text that hasn't
+          changed comes back from the cache instantly; anything the new model
+          translates differently is refreshed. It runs in the background until
+          done.
+        </v-card-text>
+        <v-card-actions>
+          <v-spacer />
+          <v-btn variant="text" @click="confirmAll = false">Cancel</v-btn>
+          <v-btn
+            color="accent" :loading="retranslating" @click="onRetranslateAll"
+          >Re-translate all</v-btn>
+        </v-card-actions>
+      </v-card>
+    </v-dialog>
+  </MaintenanceTile>
+</template>
+
+<script setup>
+import { computed, onMounted, onUnmounted, ref } from 'vue'
+import { toast } from '../../utils/toast.js'
+import { useApi } from '../../composables/useApi.js'
+import { useImportStore } from '../../stores/import.js'
+import MaintenanceTile from '../common/MaintenanceTile.vue'
+
+const api = useApi()
+const store = useImportStore()
+
+const enabled = ref(false)
+const baseUrl = ref('')
+const targetLang = ref('en')
+const busy = ref(false)
+const running = ref(false)
+const retranslating = ref(false)
+const confirmAll = ref(false)
+const testing = ref(false)
+const testResult = ref(null)   // null = not tested this session; true/false = last result
+const status = ref(null)
+const err = ref(null)
+
+// #1376 "Test translation" probe: paste text → detected lang/confidence + result.
+const probeText = ref('')
+const probing = ref(false)
+const probeResult = ref(null)
+
+// Confidence scale is Interpreter-defined (0–100 or 0–1) — show it as-is, just
+// trimmed to 2 decimals, so the operator reads the true number.
+function fmtConf (c) {
+  return c == null ? '' : Math.round(c * 100) / 100
+}
+
+const statusColor = computed(() => {
+  if (!enabled.value || !baseUrl.value) return 'grey'
+  return status.value?.healthy ? 'success' : 'error'
+})
+const statusText = computed(() => {
+  if (!enabled.value) return 'Off'
+  if (!baseUrl.value) return 'No base URL set'
+  if (status.value == null) return 'Checking…'
+  return status.value.healthy ? 'Interpreter reachable' : 'Interpreter unreachable'
+})
+
+let pollTimer = null
+async function loadStatus() {
+  try { status.value = await api.get('/api/settings/translation/status') }
+  catch { status.value = null }
+  // Poll live while a sweep is running so the remaining count ticks down; stop
+  // when idle (a fresh trigger restarts it via its own setTimeout(loadStatus)).
+  clearTimeout(pollTimer)
+  if (status.value?.active) pollTimer = setTimeout(loadStatus, 3000)
+}
+onUnmounted(() => clearTimeout(pollTimer))
+
+async function onTest() {
+  // Ping /v1/health for the CURRENTLY-typed URL (not the saved one), so a new
+  // URL can be verified before enabling. Also reflects in the status dot.
+  testing.value = true
+  err.value = null
+  testResult.value = null
+  try {
+    const r = await api.post('/api/settings/translation/test', {
+      body: { base_url: baseUrl.value.trim() },
+    })
+    testResult.value = !!r.healthy
+    if (status.value) status.value.healthy = !!r.healthy
+  } catch (e) {
+    err.value = e.message
+  } finally {
+    testing.value = false
+  }
+}
+
+async function onProbe () {
+  probing.value = true
+  err.value = null
+  probeResult.value = null
+  try {
+    probeResult.value = await api.post('/api/settings/translation/probe', {
+      body: { text: probeText.value.trim() },
+    })
+  } catch (e) {
+    err.value = e.message
+  } finally {
+    probing.value = false
+  }
+}
+
+onMounted(async () => {
+  try {
+    await store.loadSettings()
+    const s = store.settings || {}
+    enabled.value = !!s.translation_enabled
+    baseUrl.value = s.interpreter_base_url || ''
+    targetLang.value = s.translation_target_lang || 'en'
+  } catch { /* non-fatal */ }
+  await loadStatus()
+})
+
+async function save(patch) {
+  busy.value = true
+  err.value = null
+  try { await store.patchSettings(patch) }
+  catch (e) { err.value = e.message }
+  finally { busy.value = false }
+}
+
+async function onToggle(val) {
+  await save({ translation_enabled: !!val })
+  toast({ text: val ? 'Translation on' : 'Translation off', type: 'success' })
+  await loadStatus()
+}
+async function onSave() {
+  await save({
+    interpreter_base_url: baseUrl.value.trim(),
+    translation_target_lang: (targetLang.value || 'en').trim() || 'en',
+  })
+  await loadStatus()
+}
+async function onRun() {
+  running.value = true
+  err.value = null
+  try {
+    await api.post('/api/settings/translation/run')
+    toast({ text: 'Translation sweep started', type: 'success' })
+  } catch (e) {
+    err.value = e.message
+  } finally {
+    running.value = false
+    setTimeout(loadStatus, 1500)   // let the sweep make a dent, then refresh
+  }
+}
+async function onRetranslateAll() {
+  retranslating.value = true
+  err.value = null
+  try {
+    await api.post('/api/settings/translation/retranslate', { body: { all: true } })
+    confirmAll.value = false
+    toast({ text: 'Re-translating all posts…', type: 'success' })
+  } catch (e) {
+    err.value = e.message
+  } finally {
+    retranslating.value = false
+    setTimeout(loadStatus, 1500)   // reset spikes the untranslated count — refresh it
+  }
+}
+</script>

frontend/src/stores/explore.js

@@ -44,7 +44,9 @@ export const useExploreStore = defineStore('explore', () => {
       // empty and let the view explain why (anchor.has_embedding === false).
       if (detail.has_embedding) {
         const body = await api.get('/api/gallery/similar', {
-          params: { similar_to: numId, limit: NEIGHBOR_LIMIT },
+          // exclude_wip: keep work-in-progress out of the Explore rabbit-hole
+          // (the gallery's own "similar" button still shows it) — operator 2026-07-08.
+          params: { similar_to: numId, limit: NEIGHBOR_LIMIT, exclude_wip: 1 },
         })
         if (!t.isCurrent()) return
         neighbors.value = body.images || []

tests/test_api_settings.py

@@ -28,6 +28,206 @@ async def test_patch_import_settings(client):
     assert body["transparency_threshold"] == 0.7
 
 
+@pytest.mark.asyncio
+async def test_translation_settings_defaults_and_patch(client):
+    # #143: translation is OFF by default with NO default host — the operator
+    # points it at their own Interpreter proxy and enables it.
+    body = await (await client.get("/api/settings/import")).get_json()
+    assert body["translation_enabled"] is False
+    assert body["interpreter_base_url"] == ""
+    assert body["translation_target_lang"] == "en"
+
+    ok = await client.patch("/api/settings/import", json={
+        "translation_enabled": True,
+        "interpreter_base_url": "http://interpreter.lan",
+    })
+    assert ok.status_code == 200
+    out = await ok.get_json()
+    assert out["translation_enabled"] is True
+    assert out["interpreter_base_url"] == "http://interpreter.lan"
+
+    # Type validation.
+    assert (await client.patch(
+        "/api/settings/import", json={"translation_enabled": "yes"})).status_code == 400
+    assert (await client.patch(
+        "/api/settings/import", json={"interpreter_base_url": 123})).status_code == 400
+
+
+@pytest.mark.asyncio
+async def test_translation_status_defaults(client):
+    # Off + no URL → no network health call, healthy False (#143).
+    body = await (await client.get("/api/settings/translation/status")).get_json()
+    assert body["enabled"] is False
+    assert body["base_url_set"] is False
+    assert body["healthy"] is False
+    assert "untranslated_count" in body
+    assert body["active"] is False      # no sweep running
+    assert body["last_run"] is None
+
+
+@pytest.mark.asyncio
+async def test_translation_status_reports_active_and_last_run(client, db):
+    # A running translate/retranslate TaskRun → active True; the most recent
+    # finished one → last_run (task basename + status).
+    from datetime import UTC, datetime
+
+    from backend.app.models import TaskRun
+
+    db.add(TaskRun(
+        celery_task_id="r-run", queue="maintenance_long",
+        task_name="backend.app.tasks.translation.retranslate_posts",
+        started_at=datetime.now(UTC), status="running",
+    ))
+    db.add(TaskRun(
+        celery_task_id="r-done", queue="maintenance_long",
+        task_name="backend.app.tasks.translation.translate_posts",
+        started_at=datetime.now(UTC), finished_at=datetime.now(UTC),
+        status="success",
+    ))
+    await db.commit()
+    body = await (await client.get("/api/settings/translation/status")).get_json()
+    assert body["active"] is True
+    assert body["last_run"]["task"] == "translate_posts"
+    assert body["last_run"]["status"] == "success"
+
+
+@pytest.mark.asyncio
+async def test_translation_run_requires_config(client):
+    resp = await client.post("/api/settings/translation/run")
+    assert resp.status_code == 400   # disabled / no base URL
+
+
+@pytest.mark.asyncio
+async def test_translation_test_connection(client, monkeypatch):
+    # Tests a GIVEN url (not the saved one) without persisting anything.
+    monkeypatch.setattr("backend.app.api.settings.ic.health", lambda *a, **k: True)
+    resp = await client.post(
+        "/api/settings/translation/test", json={"base_url": "http://i.lan"})
+    assert resp.status_code == 200
+    assert (await resp.get_json())["healthy"] is True
+    # Empty URL → False, no health call.
+    empty = await client.post(
+        "/api/settings/translation/test", json={"base_url": ""})
+    assert (await empty.get_json())["healthy"] is False
+
+
+@pytest.mark.asyncio
+async def test_translation_run_enqueues_when_configured(client, monkeypatch):
+    sink = {}
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.translate_posts.delay",
+        lambda *a, **k: sink.update(k) or type("R", (), {"id": "t1"})(),
+    )
+    await client.patch("/api/settings/import", json={
+        "translation_enabled": True, "interpreter_base_url": "http://i.lan",
+    })
+    resp = await client.post("/api/settings/translation/run")
+    assert resp.status_code == 202
+    assert (await resp.get_json())["celery_task_id"] == "t1"
+    assert sink["drain"] is True   # "Translate now" chases the whole backlog
+
+
+@pytest.mark.asyncio
+async def test_translation_probe_requires_text(client):
+    resp = await client.post(
+        "/api/settings/translation/probe", json={"text": "  "})
+    assert resp.status_code == 400
+
+
+@pytest.mark.asyncio
+async def test_translation_probe_requires_base_url(client):
+    # Text given but no Interpreter URL saved → nothing to probe against.
+    resp = await client.post(
+        "/api/settings/translation/probe", json={"text": "hello"})
+    assert resp.status_code == 400
+
+
+@pytest.mark.asyncio
+async def test_translation_probe_returns_detection(client, monkeypatch):
+    # The diagnostic surfaces detected language + confidence + result, unsaved.
+    monkeypatch.setattr(
+        "backend.app.api.settings.ic.translate",
+        lambda texts, **k: {
+            "translations": ["Work in Progress"],
+            "detected_lang": "de", "detected_confidence": 71.5,
+            "engine": "llm", "engine_version": "v1",
+        },
+    )
+    await client.patch("/api/settings/import", json={
+        "translation_enabled": True, "interpreter_base_url": "http://i.lan",
+    })
+    resp = await client.post(
+        "/api/settings/translation/probe", json={"text": "WIP"})
+    assert resp.status_code == 200
+    body = await resp.get_json()
+    assert body["detected_lang"] == "de"
+    assert body["detected_confidence"] == 71.5
+    assert body["translated"] == "Work in Progress"
+    assert body["target"] == "en"
+
+
+def _fake_retranslate(monkeypatch, sink):
+    # Record the kwargs the endpoint enqueues with, return a fake AsyncResult.
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.retranslate_posts.delay",
+        lambda *a, **k: sink.update(k) or type("R", (), {"id": "r1"})(),
+    )
+
+
+@pytest.mark.asyncio
+async def test_translation_retranslate_requires_config(client):
+    # Disabled → 400 even with an explicit scope (no reset is enqueued).
+    resp = await client.post(
+        "/api/settings/translation/retranslate", json={"all": True})
+    assert resp.status_code == 400
+
+
+@pytest.mark.asyncio
+async def test_translation_retranslate_requires_target(client, monkeypatch):
+    # 'all' must be explicit: an empty body is a 400, so a stray call can't
+    # wipe every translation.
+    _fake_retranslate(monkeypatch, {})
+    await client.patch("/api/settings/import", json={
+        "translation_enabled": True, "interpreter_base_url": "http://i.lan",
+    })
+    resp = await client.post("/api/settings/translation/retranslate")
+    assert resp.status_code == 400
+
+
+@pytest.mark.asyncio
+async def test_translation_retranslate_artist_scope(client, monkeypatch):
+    sink = {}
+    _fake_retranslate(monkeypatch, sink)
+    await client.patch("/api/settings/import", json={
+        "translation_enabled": True, "interpreter_base_url": "http://i.lan",
+    })
+    resp = await client.post(
+        "/api/settings/translation/retranslate", json={"artist_id": 7})
+    assert resp.status_code == 202
+    assert (await resp.get_json())["celery_task_id"] == "r1"
+    assert sink["artist_ids"] == [7]
+
+
+@pytest.mark.asyncio
+async def test_translation_retranslate_all_scope(client, monkeypatch):
+    sink = {}
+    _fake_retranslate(monkeypatch, sink)
+    await client.patch("/api/settings/import", json={
+        "translation_enabled": True, "interpreter_base_url": "http://i.lan",
+    })
+    resp = await client.post(
+        "/api/settings/translation/retranslate", json={"all": True})
+    assert resp.status_code == 202
+    assert sink["artist_ids"] is None
+
+
+@pytest.mark.asyncio
+async def test_translation_retranslate_bad_artist_id(client):
+    resp = await client.post(
+        "/api/settings/translation/retranslate", json={"artist_id": "abc"})
+    assert resp.status_code == 400
+
+
 @pytest.mark.asyncio
 async def test_patch_rejects_non_object(client):
     resp = await client.patch("/api/settings/import", json=[1, 2, 3])

tests/test_gallery_similar.py

@@ -98,6 +98,30 @@ async def test_similar_excludes_presentation_tagged_images(db):
     assert {i.id for i in res_from_banner} == {src.id, wipped.id, plain.id}
 
 
+@pytest.mark.asyncio
+async def test_similar_exclude_wip_drops_wip_neighbors(db):
+    """Explore passes exclude_wip=True to also hide work-in-progress from the
+    rabbit-hole (banner is always hidden; wip only when asked)."""
+    src = await _img(db, 1, _vec(1, 0))
+    bannered = await _img(db, 2, _vec(1, 0.02))   # always hidden
+    wipped = await _img(db, 3, _vec(1, 0.3))      # hidden only with exclude_wip
+    plain = await _img(db, 4, _vec(1, 0.6))
+    banner_tag = (await db.execute(select(Tag).where(
+        Tag.is_system.is_(True), Tag.name == "banner"))).scalar_one()
+    wip_tag = (await db.execute(select(Tag).where(
+        Tag.is_system.is_(True), Tag.name == "wip"))).scalar_one()
+    await db.execute(image_tag.insert().values(
+        image_record_id=bannered.id, tag_id=banner_tag.id, source="manual"))
+    await db.execute(image_tag.insert().values(
+        image_record_id=wipped.id, tag_id=wip_tag.id, source="manual"))
+    svc = GalleryService(db)
+    res = await svc.similar(src.id, limit=10, exclude_wip=True)
+    assert [i.id for i in res] == [plain.id]        # wip + banner both gone
+    # Default (gallery "similar" button) still keeps wip (#1274).
+    res_default = await svc.similar(src.id, limit=10)
+    assert wipped.id in {i.id for i in res_default}
+
+
 @pytest.mark.asyncio
 async def test_similar_composes_with_tag_filter(db):
     src = await _img(db, 1, _vec(1, 0))

tests/test_interpreter_client.py

@@ -0,0 +1,142 @@
+"""Interpreter translation client (#143) — unit tests with mocked HTTP (no DB,
+no real network)."""
+import pytest
+
+from backend.app.services import interpreter_client as ic
+
+
+class _Resp:
+    def __init__(self, status_code=200, payload=None, headers=None):
+        self.status_code = status_code
+        self._payload = payload or {}
+        self.headers = headers or {}
+
+    def json(self):
+        return self._payload
+
+    def raise_for_status(self):
+        if self.status_code >= 400:
+            raise ic.requests.HTTPError(f"status {self.status_code}")
+
+
+def test_translate_maps_batch_in_order(monkeypatch):
+    captured = {}
+
+    def fake_post(url, json, timeout):
+        captured["json"] = json
+        return _Resp(200, {
+            "translatedText": ["The cat is cute", "Blonde gal!"],
+            "detectedLanguage": {"language": "ja", "confidence": 0.98},
+            "interpreter": {"engine": "llm", "engine_version": "ollama:x:12b"},
+        })
+
+    monkeypatch.setattr(ic.session, "post", fake_post)
+    out = ic.translate(["ねこが可愛い", "金髪ギャル！"], base_url="http://i.lan")
+    assert out["translations"] == ["The cat is cute", "Blonde gal!"]
+    assert out["detected_lang"] == "ja"
+    assert out["detected_confidence"] == 0.98   # surfaced for the detection guard
+    assert out["engine_version"] == "ollama:x:12b"
+    assert captured["json"]["q"] == ["ねこが可愛い", "金髪ギャル！"]
+    assert captured["json"]["target"] == "en"
+
+
+def test_translate_passthrough_unchanged(monkeypatch):
+    # Already-English items come back unchanged in their slot (engine "none").
+    monkeypatch.setattr(ic.session, "post", lambda *a, **k: _Resp(200, {
+        "translatedText": ["already english"],
+        "detectedLanguage": {"language": "en"},
+        "interpreter": {"engine": "none", "engine_version": None},
+    }))
+    out = ic.translate(["already english"], base_url="http://i.lan")
+    assert out["translations"] == ["already english"]
+    assert out["detected_lang"] == "en"
+    assert out["engine"] == "none"
+
+
+def test_translate_503_raises_unavailable(monkeypatch):
+    monkeypatch.setattr(ic.session, "post", lambda *a, **k: _Resp(503, {}))
+    with pytest.raises(ic.InterpreterUnavailable):
+        ic.translate(["x"], base_url="http://i.lan")
+
+
+def test_translate_connection_error_raises_unavailable(monkeypatch):
+    def boom(*a, **k):
+        raise ic.requests.ConnectionError("refused")
+
+    monkeypatch.setattr(ic.session, "post", boom)
+    with pytest.raises(ic.InterpreterUnavailable):
+        ic.translate(["x"], base_url="http://i.lan")
+
+
+@pytest.mark.parametrize("code", [429, 500, 502, 503, 504])
+def test_translate_429_and_5xx_raise_unavailable(monkeypatch, code):
+    # A gracefully-draining service behind a reverse proxy returns 429/502/503/504
+    # — all mean "retry later", not an opaque error.
+    monkeypatch.setattr(ic.session, "post", lambda *a, **k: _Resp(code, {}))
+    with pytest.raises(ic.InterpreterUnavailable) as ei:
+        ic.translate(["x"], base_url="http://i.lan")
+    assert ei.value.retry_after is None
+
+
+def test_translate_honours_retry_after_seconds(monkeypatch):
+    monkeypatch.setattr(
+        ic.session, "post",
+        lambda *a, **k: _Resp(503, {}, headers={"Retry-After": "42"}),
+    )
+    with pytest.raises(ic.InterpreterUnavailable) as ei:
+        ic.translate(["x"], base_url="http://i.lan")
+    assert ei.value.retry_after == 42
+
+
+def test_translate_retry_after_past_http_date_clamps_to_zero(monkeypatch):
+    # HTTP-date form; a past date → non-negative clamp to 0 (deterministic).
+    monkeypatch.setattr(
+        ic.session, "post",
+        lambda *a, **k: _Resp(
+            503, {}, headers={"Retry-After": "Wed, 21 Oct 2015 07:28:00 GMT"}),
+    )
+    with pytest.raises(ic.InterpreterUnavailable) as ei:
+        ic.translate(["x"], base_url="http://i.lan")
+    assert ei.value.retry_after == 0.0
+
+
+def test_translate_400_raises_bad_request(monkeypatch):
+    monkeypatch.setattr(
+        ic.session, "post", lambda *a, **k: _Resp(400, {"error": "bad target"})
+    )
+    with pytest.raises(ic.InterpreterBadRequest):
+        ic.translate(["x"], base_url="http://i.lan")
+
+
+def test_translate_empty_is_noop(monkeypatch):
+    def boom(*a, **k):
+        raise AssertionError("should not call the service for an empty batch")
+
+    monkeypatch.setattr(ic.session, "post", boom)
+    assert ic.translate([], base_url="http://i.lan")["translations"] == []
+
+
+def test_health_true_when_llm_up(monkeypatch):
+    monkeypatch.setattr(
+        ic.session, "get", lambda *a, **k: _Resp(200, {"engines": {"llm": True}})
+    )
+    assert ic.health("http://i.lan") is True
+
+
+def test_health_false_when_engine_down(monkeypatch):
+    monkeypatch.setattr(
+        ic.session, "get", lambda *a, **k: _Resp(200, {"engines": {"llm": False}})
+    )
+    assert ic.health("http://i.lan") is False
+
+
+def test_health_false_on_error(monkeypatch):
+    def boom(*a, **k):
+        raise ic.requests.ConnectionError("refused")
+
+    monkeypatch.setattr(ic.session, "get", boom)
+    assert ic.health("http://i.lan") is False
+
+
+def test_health_false_when_url_empty():
+    assert ic.health("") is False

tests/test_maintenance.py

@@ -26,6 +26,28 @@ def _make_batch(session) -> int:
     return batch.id
 
 
+def test_cleanup_orphaned_temp_files_removes_stale_only(tmp_path, monkeypatch):
+    import os
+
+    from backend.app.tasks import maintenance as m
+
+    monkeypatch.setattr(m, "IMAGES_ROOT", tmp_path)
+    stale = tmp_path / "artist" / "img.jpg.part"      # killed download → orphan
+    stale.parent.mkdir(parents=True)
+    stale.write_bytes(b"x")
+    old = datetime.now(UTC).timestamp() - 8 * 3600     # older than the 6h guard
+    os.utime(stale, (old, old))
+    fresh = tmp_path / "in_progress.jpg.partial"       # active download → keep
+    fresh.write_bytes(b"x")
+    keep = tmp_path / "real.jpg"                        # a real image → keep
+    keep.write_bytes(b"x")
+
+    assert m.cleanup_orphaned_temp_files() == 1
+    assert not stale.exists()
+    assert fresh.exists()
+    assert keep.exists()
+
+
 def test_recover_interrupted_only_old(db_sync, monkeypatch):
     batch_id = _make_batch(db_sync)
     now = datetime.now(UTC)

tests/test_post_feed_service.py

@@ -283,6 +283,30 @@ async def test_scroll_item_shape_minimal(db):
     assert "description_full" not in item
 
 
+@pytest.mark.asyncio
+async def test_scroll_surfaces_translation_fields(db):
+    # #143: a translated post exposes the translated title/description + source
+    # lang, with the originals still present for the toggle.
+    artist = await _seed_artist(db, "alice-tr")
+    src = await _seed_source(db, artist.id, "pixiv", "https://p/alice-tr")
+    p = await _seed_post(
+        db, src.id, external_id="TR", post_date=datetime.now(UTC),
+        title="ねこ", description="<p>かわいい</p>",
+    )
+    p.post_title_translated = "cat"
+    p.description_translated = "cute"
+    p.translated_source_lang = "ja"
+    await db.commit()
+
+    page = await PostFeedService(db).scroll(cursor=None, limit=10)
+    item = page["items"][0]
+    assert item["post_title_translated"] == "cat"
+    assert item["description_translated"] == "cute"
+    assert item["translated_source_lang"] == "ja"
+    assert item["post_title"] == "ねこ"           # original kept for the toggle
+    assert item["description_plain"] == "かわいい"
+
+
 @pytest.mark.asyncio
 async def test_scroll_description_truncates_long_text(db):
     artist = await _seed_artist(db, "alice-long")

tests/test_translate_posts.py

@@ -0,0 +1,415 @@
+"""translate_posts sweep (#143) — integration, with a stubbed Interpreter client
+and the task's session factory pointed at the test's db_sync."""
+import pytest
+from sqlalchemy import select
+
+from backend.app.models import Artist, ImportSettings, Post
+from backend.app.services import interpreter_client as ic
+from backend.app.tasks.translation import (
+    _RETRANSLATE_COUNTDOWN,
+    retranslate_posts,
+    translate_posts,
+)
+
+pytestmark = pytest.mark.integration
+
+
+class _Ctx:
+    def __init__(self, s):
+        self.s = s
+
+    def __enter__(self):
+        return self.s
+
+    def __exit__(self, *a):
+        return False
+
+
+def _sf(db_sync):
+    class _SM:
+        def __call__(self):
+            return _Ctx(db_sync)
+
+    return _SM()
+
+
+def _artist(db, name="A", slug="a"):
+    a = Artist(name=name, slug=slug)
+    db.add(a)
+    db.flush()
+    return a
+
+
+def _post(db, artist_id, *, title=None, desc=None, ext="p1"):
+    p = Post(
+        artist_id=artist_id, external_post_id=ext,
+        post_title=title, description=desc,
+    )
+    db.add(p)
+    db.flush()
+    return p
+
+
+def _mark_translated(p, *, lang="ja", ver="v1"):
+    """Simulate a prior (old-model) translation so retranslate has something to
+    reset."""
+    p.post_title_translated = "OLD"
+    p.description_translated = "OLD"
+    p.translated_source_lang = lang
+    p.translation_engine_version = ver
+
+
+def _enable(db, url="http://i.lan"):
+    cfg = db.execute(
+        select(ImportSettings).where(ImportSettings.id == 1)
+    ).scalar_one()
+    cfg.translation_enabled = True
+    cfg.interpreter_base_url = url
+    db.flush()
+
+
+def _patch(monkeypatch, db_sync):
+    monkeypatch.setattr(
+        "backend.app.tasks.translation._sync_session_factory",
+        lambda: _sf(db_sync),
+    )
+
+
+def test_translate_posts_stores_translation(db_sync, monkeypatch):
+    _patch(monkeypatch, db_sync)
+    monkeypatch.setattr("backend.app.tasks.translation.ic.health", lambda *a, **k: True)
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.ic.translate",
+        lambda texts, **k: {
+            "translations": [f"EN:{t}" for t in texts],
+            "detected_lang": "ja", "engine": "llm", "engine_version": "v1",
+        },
+    )
+    a = _artist(db_sync)
+    p = _post(db_sync, a.id, title="ねこ", desc="かわいい")
+    _enable(db_sync)
+    db_sync.commit()
+
+    assert "translated=1" in translate_posts()
+    db_sync.refresh(p)
+    assert p.post_title_translated == "EN:ねこ"
+    assert p.description_translated == "EN:かわいい"
+    assert p.translated_source_lang == "ja"
+    assert p.translation_engine_version == "v1"
+
+
+def test_translate_posts_passthrough_english_marks_handled(db_sync, monkeypatch):
+    _patch(monkeypatch, db_sync)
+    monkeypatch.setattr("backend.app.tasks.translation.ic.health", lambda *a, **k: True)
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.ic.translate",
+        lambda texts, **k: {
+            "translations": list(texts), "detected_lang": "en",
+            "engine": "none", "engine_version": None,
+        },
+    )
+    a = _artist(db_sync)
+    p = _post(db_sync, a.id, title="hello world", ext="p2")
+    _enable(db_sync)
+    db_sync.commit()
+
+    translate_posts()
+    db_sync.refresh(p)
+    assert p.translated_source_lang == "en"     # marked handled...
+    assert p.post_title_translated is None       # ...but nothing to show
+
+
+def test_translate_posts_mixed_language_translates_nonenglish_field(db_sync, monkeypatch):
+    # English title + Japanese description: the description is still translated
+    # even though the title is already English (per-field detection, not the old
+    # aggregate first-item bail). Source lang comes from the translated field.
+    _patch(monkeypatch, db_sync)
+    monkeypatch.setattr("backend.app.tasks.translation.ic.health", lambda *a, **k: True)
+
+    def fake_translate(texts, **k):
+        t = texts[0]
+        if t.isascii():   # already English → passthrough
+            return {"translations": [t], "detected_lang": "en",
+                    "engine": "none", "engine_version": None}
+        return {"translations": [f"EN:{t}"], "detected_lang": "ja",
+                "engine": "llm", "engine_version": "v9"}
+
+    monkeypatch.setattr("backend.app.tasks.translation.ic.translate", fake_translate)
+    a = _artist(db_sync)
+    p = _post(db_sync, a.id, title="hello", desc="ねこ")
+    _enable(db_sync)
+    db_sync.commit()
+
+    assert "translated=1" in translate_posts()
+    db_sync.refresh(p)
+    assert p.post_title_translated is None          # English title untouched
+    assert p.description_translated == "EN:ねこ"      # Japanese desc translated
+    assert p.translated_source_lang == "ja"          # from the translated field
+    assert p.translation_engine_version == "v9"
+
+
+def test_translate_posts_disabled_is_noop(db_sync, monkeypatch):
+    _patch(monkeypatch, db_sync)
+    a = _artist(db_sync)
+    p = _post(db_sync, a.id, title="ねこ", ext="p3")
+    db_sync.commit()   # translation_enabled defaults False
+    assert translate_posts() == "disabled"
+    db_sync.refresh(p)
+    assert p.translated_source_lang is None
+
+
+def test_translate_posts_service_down_leaves_untranslated(db_sync, monkeypatch):
+    _patch(monkeypatch, db_sync)
+    monkeypatch.setattr("backend.app.tasks.translation.ic.health", lambda *a, **k: False)
+    a = _artist(db_sync)
+    p = _post(db_sync, a.id, title="ねこ", ext="p4")
+    _enable(db_sync)
+    db_sync.commit()
+    assert translate_posts() == "interpreter unavailable"
+    db_sync.refresh(p)
+    assert p.translated_source_lang is None       # will retry next run
+
+
+def test_translate_posts_interrupt_reenqueues_after_backoff(db_sync, monkeypatch):
+    # A drain mid-sweep (health passed, translate 503s w/ Retry-After) re-enqueues
+    # the daily sweep after the backoff instead of waiting for tomorrow's beat.
+    _patch(monkeypatch, db_sync)
+    monkeypatch.setattr("backend.app.tasks.translation.ic.health", lambda *a, **k: True)
+
+    def _drain(texts, **k):
+        raise ic.InterpreterUnavailable("draining", retry_after=30)
+
+    monkeypatch.setattr("backend.app.tasks.translation.ic.translate", _drain)
+    calls = []
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.translate_posts.apply_async",
+        lambda *a, **k: calls.append((a, k)),
+    )
+    a = _artist(db_sync)
+    _post(db_sync, a.id, title="ねこ", ext="p1")
+    _enable(db_sync)
+    db_sync.commit()
+
+    assert "interrupted" in translate_posts()
+    assert len(calls) == 1
+    assert calls[0][1]["countdown"] == 30
+
+
+def _mock_ok(monkeypatch):
+    monkeypatch.setattr("backend.app.tasks.translation.ic.health", lambda *a, **k: True)
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.ic.translate",
+        lambda texts, **k: {
+            "translations": [f"EN:{t}" for t in texts],
+            "detected_lang": "ja", "engine": "llm", "engine_version": "v1",
+        },
+    )
+
+
+def test_translate_posts_drain_chases_tail(db_sync, monkeypatch):
+    # "Translate now" (drain=True): with the chunk capped at 1 and 2 untranslated
+    # posts, the first chunk re-enqueues itself — drain preserved — to finish the
+    # backlog rather than waiting for the next beat.
+    _patch(monkeypatch, db_sync)
+    _mock_ok(monkeypatch)
+    monkeypatch.setattr("backend.app.tasks.translation._MAX_POSTS_PER_RUN", 1)
+    calls = []
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.translate_posts.apply_async",
+        lambda *a, **k: calls.append((a, k)),
+    )
+    a = _artist(db_sync)
+    _post(db_sync, a.id, title="ねこ", ext="p1")
+    _post(db_sync, a.id, title="いぬ", ext="p2")
+    _enable(db_sync)
+    db_sync.commit()
+
+    translate_posts(drain=True)
+    assert len(calls) == 1                       # one re-enqueue for the tail
+    args, kw = calls[0]
+    assert args[1] == {"drain": True}            # drain flag carried forward
+    assert kw["countdown"] == _RETRANSLATE_COUNTDOWN
+
+
+def test_translate_posts_beat_single_chunk_no_tail_chase(db_sync, monkeypatch):
+    # The periodic beat (drain defaults False) does exactly ONE chunk and never
+    # re-enqueues — the 8h cadence drives the rest.
+    _patch(monkeypatch, db_sync)
+    _mock_ok(monkeypatch)
+    monkeypatch.setattr("backend.app.tasks.translation._MAX_POSTS_PER_RUN", 1)
+    calls = []
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.translate_posts.apply_async",
+        lambda *a, **k: calls.append((a, k)),
+    )
+    a = _artist(db_sync)
+    _post(db_sync, a.id, title="ねこ", ext="p1")
+    _post(db_sync, a.id, title="いぬ", ext="p2")
+    _enable(db_sync)
+    db_sync.commit()
+
+    translate_posts()                            # drain=False
+    assert calls == []                           # no self-re-enqueue
+
+
+def _mock_new_model(monkeypatch, *, ver="v2"):
+    """Interpreter is up and translates with a NEW engine version."""
+    monkeypatch.setattr("backend.app.tasks.translation.ic.health", lambda *a, **k: True)
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.ic.translate",
+        lambda texts, **k: {
+            "translations": [f"NEW:{t}" for t in texts],
+            "detected_lang": "ja", "engine": "llm", "engine_version": ver,
+        },
+    )
+
+
+def test_retranslate_resets_and_reruns(db_sync, monkeypatch):
+    # A post translated by the old model gets cleared + re-run through the new
+    # one (new engine_version proves the reset happened, not a cache short-circuit).
+    _patch(monkeypatch, db_sync)
+    _mock_new_model(monkeypatch)
+    a = _artist(db_sync)
+    p = _post(db_sync, a.id, title="ねこ", desc="かわいい")
+    _mark_translated(p)
+    _enable(db_sync)
+    db_sync.commit()
+
+    retranslate_posts(artist_ids=[a.id])
+    db_sync.refresh(p)
+    assert p.post_title_translated == "NEW:ねこ"
+    assert p.description_translated == "NEW:かわいい"
+    assert p.translation_engine_version == "v2"
+
+
+def test_retranslate_artist_scope_leaves_others(db_sync, monkeypatch):
+    # Scoping to one artist must not touch another artist's translations.
+    _patch(monkeypatch, db_sync)
+    _mock_new_model(monkeypatch)
+    a1 = _artist(db_sync)
+    a2 = _artist(db_sync, name="B", slug="b")
+    p1 = _post(db_sync, a1.id, title="ねこ", ext="p1")
+    p2 = _post(db_sync, a2.id, title="いぬ", ext="p2")
+    _mark_translated(p1)
+    _mark_translated(p2)
+    _enable(db_sync)
+    db_sync.commit()
+
+    retranslate_posts(artist_ids=[a1.id])
+    db_sync.refresh(p1)
+    db_sync.refresh(p2)
+    assert p1.post_title_translated == "NEW:ねこ"     # re-run
+    assert p1.translation_engine_version == "v2"
+    assert p2.post_title_translated == "OLD"          # untouched
+    assert p2.translation_engine_version == "v1"
+
+
+def test_retranslate_runs_until_done(db_sync, monkeypatch):
+    # With the chunk capped at 1 and 2 posts to redo, the first chunk re-enqueues
+    # itself (with _reset_done=True so it doesn't wipe the fresh work) to finish.
+    _patch(monkeypatch, db_sync)
+    _mock_new_model(monkeypatch)
+    monkeypatch.setattr("backend.app.tasks.translation._MAX_POSTS_PER_RUN", 1)
+    calls = []
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.retranslate_posts.apply_async",
+        lambda *a, **k: calls.append((a, k)),
+    )
+    a = _artist(db_sync)
+    p1 = _post(db_sync, a.id, title="ねこ", ext="p1")
+    p2 = _post(db_sync, a.id, title="いぬ", ext="p2")
+    _mark_translated(p1)
+    _mark_translated(p2)
+    _enable(db_sync)
+    db_sync.commit()
+
+    retranslate_posts(artist_ids=[a.id])
+    assert len(calls) == 1                             # one re-enqueue for the tail
+    args, _kw = calls[0]
+    assert args[1]["_reset_done"] is True
+    assert args[1]["artist_ids"] == [a.id]
+
+
+def test_retranslate_disabled_does_not_reset(db_sync, monkeypatch):
+    # Never wipe translations we can't rebuild — a disabled service leaves them.
+    _patch(monkeypatch, db_sync)
+    a = _artist(db_sync)
+    p = _post(db_sync, a.id, title="ねこ", ext="p1")
+    _mark_translated(p)
+    db_sync.commit()   # translation_enabled defaults False
+    assert retranslate_posts(artist_ids=[a.id]) == "disabled"
+    db_sync.refresh(p)
+    assert p.translated_source_lang == "ja"
+    assert p.post_title_translated == "OLD"
+
+
+def test_retranslate_unhealthy_does_not_reset(db_sync, monkeypatch):
+    _patch(monkeypatch, db_sync)
+    monkeypatch.setattr("backend.app.tasks.translation.ic.health", lambda *a, **k: False)
+    a = _artist(db_sync)
+    p = _post(db_sync, a.id, title="ねこ", ext="p1")
+    _mark_translated(p)
+    _enable(db_sync)
+    db_sync.commit()
+    assert retranslate_posts(artist_ids=[a.id]) == "interpreter unavailable"
+    db_sync.refresh(p)
+    assert p.translated_source_lang == "ja"
+    assert p.post_title_translated == "OLD"
+
+
+def test_retranslate_interrupt_resumes_after_retry_after(db_sync, monkeypatch):
+    # Interpreter drains mid-chunk (health passed, then translate 503s with a
+    # Retry-After): the bulk re-translate re-enqueues itself after the hinted
+    # backoff, with _reset_done=True so it never re-wipes fresh work — instead of
+    # stalling until the daily beat.
+    _patch(monkeypatch, db_sync)
+    monkeypatch.setattr("backend.app.tasks.translation.ic.health", lambda *a, **k: True)
+
+    def _drain(texts, **k):
+        raise ic.InterpreterUnavailable("draining", retry_after=42)
+
+    monkeypatch.setattr("backend.app.tasks.translation.ic.translate", _drain)
+    calls = []
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.retranslate_posts.apply_async",
+        lambda *a, **k: calls.append((a, k)),
+    )
+    a = _artist(db_sync)
+    p = _post(db_sync, a.id, title="ねこ", ext="p1")
+    _mark_translated(p)
+    _enable(db_sync)
+    db_sync.commit()
+
+    assert "interrupted" in retranslate_posts(artist_ids=[a.id])
+    assert len(calls) == 1                             # resume re-enqueued
+    args, kw = calls[0]
+    assert args[1]["_reset_done"] is True
+    assert args[1]["artist_ids"] == [a.id]
+    assert kw["countdown"] == 42                       # honoured the Retry-After
+    db_sync.refresh(p)
+    assert p.translated_source_lang is None            # reset happened, not re-run
+
+
+def test_retranslate_interrupt_default_backoff_without_hint(db_sync, monkeypatch):
+    # No Retry-After header → fall back to the default backoff (60s).
+    _patch(monkeypatch, db_sync)
+    monkeypatch.setattr("backend.app.tasks.translation.ic.health", lambda *a, **k: True)
+
+    def _drain(texts, **k):
+        raise ic.InterpreterUnavailable("draining")
+
+    monkeypatch.setattr("backend.app.tasks.translation.ic.translate", _drain)
+    calls = []
+    monkeypatch.setattr(
+        "backend.app.tasks.translation.retranslate_posts.apply_async",
+        lambda *a, **k: calls.append((a, k)),
+    )
+    a = _artist(db_sync)
+    p = _post(db_sync, a.id, title="ねこ", ext="p1")
+    _mark_translated(p)
+    _enable(db_sync)
+    db_sync.commit()
+
+    retranslate_posts(artist_ids=[a.id])
+    assert len(calls) == 1
+    assert calls[0][1]["countdown"] == 60