fix(ingest): skip tier-gated Patreon posts entirely (#874)

Patreon serves only blurred locked-preview thumbnails for posts the
authenticated account can't fully view; the native ingester was
downloading those as real media. current_user_can_view was already in
_FIELDS_POST but never read.

Add PatreonClient.post_is_gated (gate ONLY on explicit
current_user_can_view=False; missing/None → viewable, never over-filter)
and skip gated posts at the top of the ingest_core run() and preview()
loops — no media download AND no post-record stub (operator: 'no stub
for gated content'). Skipped before the post-record block so gated posts
never inflate the #862 body canary; surfaced as 'N gated-skipped' in the
run summary. Same gate in preview() for preview/apply parity (rule 93).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/app/services/ingest_core.py

@@ -155,6 +155,11 @@ class Ingester:
         # comes from the per-media sidecar (gallery-dl path). See [[post-first-ingest-contract]].
         post_record_key = getattr(self.client, "post_record_key", None)
         write_post_record = getattr(self.downloader, "write_post_record", None)
+        # #874: optional client seam — skip tier-gated posts (the account can't
+        # view them, so Patreon serves only blurred locked-preview media) ENTIRELY:
+        # no media download, no post-record stub. Absent on stub/not-yet-migrated
+        # clients → nothing is ever treated as gated.
+        post_is_gated = getattr(self.client, "post_is_gated", None)
         start = time.monotonic()
         last_live = start  # plan #709: last live-progress write timestamp
         log_lines: list[str] = []
@@ -177,6 +182,9 @@ class Ingester:
         # this walk; posts_with_body = how many yielded a non-empty body.
         posts_recorded = 0
         posts_with_body = 0
+        # Tier-gated posts skipped entirely this walk (#874) — surfaced in the
+        # run summary for diagnostics ("a lot of these now").
+        gated_skipped = 0
         # Net-new posts THIS chunk for the live progress badge (plan #704 #5);
         # excludes the re-walked resume page so _backfill_posts stays a monotonic
         # absolute across chunks instead of an inflating sum. posts_processed
@@ -270,6 +278,20 @@ class Ingester:
                 # resume_cursor None, so everything counts.
                 if not (resume_cursor and page_cursor == resume_cursor):
                     chunk_new_posts += 1
+                # Tier-gated post (#874): the account can't fully view it, so
+                # Patreon serves only blurred locked-preview media. Skip it
+                # ENTIRELY — no media download AND no post-record stub (operator
+                # decision: gated content leaves no trace; a later walk re-ingests
+                # it for real once access is gained). Skipped BEFORE the
+                # post-record block so gated posts never inflate the #862 body
+                # canary's sample. post_is_gated gates only on an explicit
+                # current_user_can_view=False (missing/None → viewable).
+                if post_is_gated and post_is_gated(post):
+                    gated_skipped += 1
+                    log_lines.append(
+                        f"  post {post.get('id')} — gated (skipped, no access)"
+                    )
+                    continue
                 # Capture the post body + external links ONCE per post (gated by
                 # the synthetic post key in the seen-ledger), for EVERY post —
                 # whether or not it has downloadable media. This is what makes a
@@ -449,6 +471,7 @@ class Ingester:
             # threshold, surfacing the ratio makes a partial extraction regression
             # visible in the Raw stdout (e.g. "bodies 3/180" reads as off).
             + (f", bodies {posts_with_body}/{posts_recorded}" if posts_recorded else "")
+            + (f", {gated_skipped} gated-skipped" if gated_skipped else "")
             + (", reached end" if reached_bottom else "")
             + (", time-boxed" if budget_hit else "")
         )
@@ -534,6 +557,10 @@ class Ingester:
         sample: list[dict] = []
         unset = object()
         last_page: object = unset
+        # #874: same gated-post gate as run() — the preview must not count
+        # blurred locked-preview media as "new", or it would overstate a gated
+        # source's backlog (preview/apply parity, rule 93).
+        post_is_gated = getattr(self.client, "post_is_gated", None)
         for post, included, page_cursor in self.client.iter_posts(
             campaign_id, cursor=None
         ):
@@ -545,6 +572,8 @@ class Ingester:
                     pages_scanned = page_limit
                     break
             posts_scanned += 1
+            if post_is_gated and post_is_gated(post):
+                continue
             media = self.client.extract_media(post, included)
             if not media:
                 continue