feat: a tick keeps looking back 30 days, so an EDITED post is reached (4386)

Operator, 2026-09-23, on a Floppystack post: "this post has been updated as
he implements hot fixes — any chance we have a way to scan for or see updated
posts so we can update ours to match and pull the new attachments and
pictures etc."

The download half already worked: extract_media reads the media list off the
LIVE feed response every walk, so a newly attached hotfix build is a ledger
key we have never seen. Only REACHING the post was missing — a tick stopped
after 20 contiguous already-have-it items, and a post edited three days after
publication sits well below twenty. Not a bug in the early-out; a count
cannot express "recent".

The early-out now needs BOTH conditions: the run of seen items AND a post
published before the horizon. Strictly a widening — window 0 is exactly the
old behaviour, and no window can make a tick stop EARLIER than it used to, so
a source paused for months still walks its whole unseen backlog. The horizon
is a floor on how far to look, never a ceiling.

Inside the window the post-record gate is bypassed too (write_post_record
revisit=True): the body is re-read from the feed response already in hand, so
a revisit costs zero requests, and a body that comes back empty writes
NOTHING rather than blanking one a detail-fetch had filled. Revisits are kept
out of the #862 body-drift canary's sample for the same reason — an empty
revisit is healthy, and counting it would walk the alarm toward firing on
good ticks.

The run summary names what changed ("3 post(s) updated (5 new file(s))") with
a line per post; the ask was to SEE updated posts, not only to end up with
their bytes.

download_revisit_days is a settings row, not a constant (rule 25) — how long
a creator keeps editing is a property of the creator. Default 30, 0 turns it
off. Migration 0108.

Also corrects two stale docstrings: both clients described post_meta as
feeding an Ingester.preview that no longer calls it. It had no consumer at
all until this change.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LVjrnpQjRgHdvq95rASoiR

backend/app/services/patreon_downloader.py

@@ -340,7 +340,7 @@ class PatreonDownloader(BaseNativeDownloader):
 
     def _write_sidecar_data(
         self, post: dict, sidecar_path: Path, *, source_url: str | None = None,
-        minimal: bool = False,
+        minimal: bool = False, detail_fetch: bool = True,
     ) -> Path:
         """Serialize the post's metadata to `sidecar_path`. The post-only record
         (`write_post_record`) writes the FULL post (body/title/date/url); the
@@ -364,7 +364,13 @@ class PatreonDownloader(BaseNativeDownloader):
         # dict — so a multi-image post fetches detail at most once, the post-record
         # body-length read reuses it, and a fully-seen post (no fresh download → no
         # sidecar write) never pays the extra GET.
-        if (not content or not content.strip()) and self._content_fetcher:
+        # `detail_fetch=False` on a REVISIT (a post inside the tick's revisit
+        # window that we already captured): re-read the body from the feed
+        # response we are holding and pay nothing. Without this a 30-day window
+        # would buy one detail GET per body-less post per tick, forever — a
+        # per-creator cost that grows with how prolific they are, to re-fetch a
+        # body we already stored.
+        if (not content or not content.strip()) and self._content_fetcher and detail_fetch:
             fetched = self._content_fetcher(str(post.get("id") or ""))
             if fetched:
                 content = fetched
@@ -386,7 +392,9 @@ class PatreonDownloader(BaseNativeDownloader):
         sidecar_path.write_text(json.dumps(data, indent=2))
         return sidecar_path
 
-    def write_post_record(self, post: dict, artist_slug: str) -> PostRecordOutcome:
+    def write_post_record(
+        self, post: dict, artist_slug: str, *, revisit: bool = False,
+    ) -> PostRecordOutcome:
         """Write a post-ONLY sidecar (no media file) for a media-less post, so
         the importer can still upsert the Post + its body — text posts often hold
         the only copy of an external <a href> link. Named `_post.json`: the
@@ -397,6 +405,18 @@ class PatreonDownloader(BaseNativeDownloader):
         Returns a PostRecordOutcome (path None when the post has no id) carrying
         the captured body's shape — post_type + final char count — so the engine
         can log per-post handling without re-reading the post itself.
+
+        `revisit=True` is the tick re-reading a post it already captured
+        (ingest_core's revisit window, #...). Two differences, both about not
+        making an update cost more than it is worth:
+
+        * no detail-fetch — the body comes from the feed response already in
+          hand, so a revisit costs zero requests;
+        * a body that comes back empty writes NOTHING and returns `path=None`.
+          On a first capture an empty body is the truth about the post; on a
+          revisit it usually just means this post's body only ever came from
+          the detail endpoint we just declined to call, and writing it would
+          blank a stored body to say something we never learned.
         """
         attrs = post.get("attributes") or {}
         title = attrs.get("title") if isinstance(attrs.get("title"), str) else None
@@ -406,9 +426,17 @@ class PatreonDownloader(BaseNativeDownloader):
             return PostRecordOutcome(
                 path=None, post_type=post_type, title=title, body_chars=0,
             )
+        if revisit:
+            feed_body = post_body_html(attrs)
+            if not (isinstance(feed_body, str) and feed_body.strip()):
+                return PostRecordOutcome(
+                    path=None, post_type=post_type, title=title, body_chars=0,
+                )
         post_dir = self.images_root / artist_slug / "patreon" / post_dir_name(post)
         post_dir.mkdir(parents=True, exist_ok=True)
-        path = self._write_sidecar_data(post, post_dir / "_post.json")
+        path = self._write_sidecar_data(
+            post, post_dir / "_post.json", detail_fetch=not revisit,
+        )
         # _write_sidecar_data has by now memoized any detail-fetched body onto
         # post["attributes"]["content"], so re-read it for the FINAL char count.
         body = (post.get("attributes") or {}).get("content")