feat(modal): autofocus tag input, expand general suggestions, retire copyright/artist categories

Four coupled operator-asked changes to the view modal (Scribe plan #509):

1. **Autofocus tag entry on modal open** — TagAutocomplete grabs focus
   in onMounted/nextTick so the caret is in the input the moment the
   modal renders. No click needed to start typing.

2. **General suggestions expanded by default** — SuggestionsPanel's
   general-category group now mounts with `:default-open="true"`.
   Operator can collapse if too noisy, but the v1 frame shows them.

3. **Lower general threshold default 0.95 → 0.50** — MLSettings.
   suggestion_threshold_general default matches character. Alembic
   0029 also bumps the existing singleton row's value if it's still
   at the old 0.95. Operator can re-tune from Settings → ML.

4. **Retire `copyright` + `artist` as ML suggestion categories** —
   neither feeds a Tag.kind (`artist` retired in FC-2d-vii-c, never
   really existed as a copyright tag-kind). They were surfaced in the
   suggestions pipeline + threshold settings UI but had no follow-
   through. Drop from SURFACED_CATEGORIES, suggestions._threshold_for,
   ml_admin GET/PATCH allowlist, MLSettings columns (alembic 0029
   drops the two columns), frontend CATEGORY_ORDER + CATEGORY_LABELS,
   SuggestionsPanel.peopleCats, AliasPickerDialog kind-check, and
   MLThresholdSliders rows.

Out of scope (intentional): `tag_kind` Postgres enum still includes
`artist` for historic Tag row queryability (per the model comment);
no operator pain reported, no enum-shrink needed.

Tests:
- test_surfaced_categories asserts {character, general}, excludes
  artist + copyright.
- test_threshold_for_artist_is_unsurfaced extended to cover copyright.
- test_get_and_patch_settings asserts new 0.50 default and the absent
  artist + copyright keys in the GET payload.

backend/app/api/ml_admin.py

@@ -9,9 +9,7 @@ ml_admin_bp = Blueprint("ml_admin", __name__, url_prefix="/api/ml")
 
 
 _EDITABLE = (
-    "suggestion_threshold_artist",
     "suggestion_threshold_character",
-    "suggestion_threshold_copyright",
     "suggestion_threshold_general",
     "centroid_similarity_threshold",
     "min_reference_images",
@@ -28,9 +26,7 @@ async def get_settings():
         ).scalar_one()
     return jsonify(
         {
-            "suggestion_threshold_artist": s.suggestion_threshold_artist,
             "suggestion_threshold_character": s.suggestion_threshold_character,
-            "suggestion_threshold_copyright": s.suggestion_threshold_copyright,
             "suggestion_threshold_general": s.suggestion_threshold_general,
             "centroid_similarity_threshold": s.centroid_similarity_threshold,
             "min_reference_images": s.min_reference_images,

backend/app/models/ml_settings.py

@@ -15,17 +15,14 @@ class MLSettings(Base):
     __table_args__ = (CheckConstraint("id = 1", name="singleton"),)
 
     id: Mapped[int] = mapped_column(Integer, primary_key=True)
-    suggestion_threshold_artist: Mapped[float] = mapped_column(
-        Float, nullable=False, default=0.30
-    )
     suggestion_threshold_character: Mapped[float] = mapped_column(
         Float, nullable=False, default=0.50
     )
-    suggestion_threshold_copyright: Mapped[float] = mapped_column(
-        Float, nullable=False, default=0.50
-    )
+    # Default lowered 0.95 → 0.50 on 2026-06-01 — operator-flagged that
+    # 0.95 hid most general suggestions. Operator-tunable via Settings →
+    # ML if too noisy.
     suggestion_threshold_general: Mapped[float] = mapped_column(
-        Float, nullable=False, default=0.95
+        Float, nullable=False, default=0.50
     )
     centroid_similarity_threshold: Mapped[float] = mapped_column(
         Float, nullable=False, default=0.55

backend/app/services/ml/suggestions.py

@@ -48,11 +48,11 @@ class SuggestionService:
         ).scalar_one()
 
     def _threshold_for(self, s: MLSettings, category: str) -> float:
-        # 'artist' intentionally absent (FC-2d-vii-c) — falls through to
-        # the 1.01 "never surfaces" default like any unsurfaced category.
+        # 'artist' (FC-2d-vii-c) and 'copyright' (2026-06-01) retired;
+        # both fall through to the 1.01 "never surfaces" default like any
+        # unsurfaced category.
         return {
             "character": s.suggestion_threshold_character,
-            "copyright": s.suggestion_threshold_copyright,
             "general": s.suggestion_threshold_general,
         }.get(category, 1.01)
 

backend/app/services/ml/tagger.py

@@ -38,10 +38,13 @@ STORE_FLOOR = float(os.environ.get("TAGGER_STORE_FLOOR", "0.05"))
 
 # The categories FC-2b surfaces in the UI. Others (meta/rating/year) are
 # still stored but the suggestion service filters them out.
-# FC-2d-vii-c: 'artist' retired — artist identity is acquisition-derived
-# (image_record.artist_id), never ML-inferred. Raw predictions are still
-# stored at STORE_FLOOR but artist never surfaces.
-SURFACED_CATEGORIES = {"character", "copyright", "general"}
+# 'artist' retired in FC-2d-vii-c — artist identity is acquisition-derived
+# (image_record.artist_id), never ML-inferred. 'copyright' retired
+# 2026-06-01 — operator doesn't use the copyright tag-kind; fandom is
+# this app's franchise/series concept (per TagsView.vue's doc comment).
+# Raw predictions for both categories still get stored at STORE_FLOOR but
+# don't surface in suggestions.
+SURFACED_CATEGORIES = {"character", "general"}
 
 # ImageNet preprocessing constants (per Camie v2 onnx_inference.py).
 _IMAGENET_MEAN = np.array([0.485, 0.456, 0.406], dtype=np.float32)