fix(provenance): scope attachments to originating post + scroll-cap the list

The Attachments section aggregated PostAttachment rows across EVERY post an
image was pHash-linked to. When one of those was a 'High Resolution Files'
mega-bundle (dozens of unrelated archives), the list ballooned past the
viewport and overwhelmed the modal's right rail.

- for_image() now scopes attachments to ImageRecord.primary_post_id (the post
  the file was actually captured from), falling back to all linked posts only
  when primary_post_id is unset (older rows / filesystem imports).
- ProvenancePanel wraps the list in a max-height scroll container with a count
  in the heading, mirroring the cards' independent-scroll treatment.

Note: FC stores archives as opaque blobs and never records which archive an
extracted image came from, so attachments can't yet be scoped tighter than the
post. Capturing image->archive containment is tracked as separate work.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

backend/app/services/provenance_service.py

@@ -85,7 +85,22 @@ class ProvenanceService:
         )
         rows = (await self.session.execute(stmt)).all()
         post_ids = [ip.post_id for ip, _p, _s, _a in rows]
-        attachments = await self._attachments_for_posts(post_ids)
+        # Scope attachments to the image's ORIGINATING post only, not every
+        # post it's pHash-linked to. An image dupe gets a provenance row per
+        # post it reappears in (enrich-on-duplicate), and one of those is
+        # often a "High Resolution Files" mega-bundle carrying dozens of
+        # unrelated archives — aggregating across all linked posts ballooned
+        # the panel with files that have nothing to do with this image.
+        # primary_post_id is the post this file was actually captured from;
+        # fall back to all linked posts only when it's unset (older rows /
+        # filesystem imports). NB: FC stores archives as opaque blobs and
+        # never records which archive an extracted image came from, so we
+        # cannot scope tighter than the post — see milestone for the
+        # image->archive capture work.
+        attach_post_ids = (
+            [rec.primary_post_id] if rec.primary_post_id is not None else post_ids
+        )
+        attachments = await self._attachments_for_posts(attach_post_ids)
         return {
             "image_id": image_id,
             "provenance": [

frontend/src/components/modal/ProvenancePanel.vue

@@ -70,14 +70,19 @@
     </div>
 
     <div v-if="attachments.length" class="fc-prov__attach">
-      <h4 class="fc-prov__attach-title">Attachments</h4>
-      <a
-        v-for="at in attachments" :key="at.id"
-        class="fc-prov__attach-row"
-        :href="at.download_url" :download="at.original_filename"
-      >⬇ {{ at.original_filename }}
-        <span class="fc-prov__attach-size">({{ at.size_bytes }} B)</span>
-      </a>
+      <h4 class="fc-prov__attach-title">Attachments ({{ attachments.length }})</h4>
+      <!-- Scroll-capped: a single post can carry dozens of archives (HR
+           bundle posts), which previously ballooned the panel past the
+           viewport. Mirror the cards' independent-scroll treatment. -->
+      <div class="fc-prov__attach-list">
+        <a
+          v-for="at in attachments" :key="at.id"
+          class="fc-prov__attach-row"
+          :href="at.download_url" :download="at.original_filename"
+        >⬇ {{ at.original_filename }}
+          <span class="fc-prov__attach-size">({{ at.size_bytes }} B)</span>
+        </a>
+      </div>
     </div>
   </section>
 </template>
@@ -229,6 +234,15 @@ function openPost(postId, artistId) {
   font-size: 13px; color: rgb(var(--v-theme-on-surface-variant));
   margin: 8px 0 4px;
 }
+.fc-prov__attach-list {
+  /* ~7 rows visible before scrolling; the clipped row hints at more.
+     Hairline scrollbar matching .fc-prov__cards. */
+  max-height: 180px;
+  overflow-y: auto;
+  scrollbar-width: thin;
+  scrollbar-color: rgb(var(--v-theme-surface-light)) transparent;
+  padding-right: 4px;
+}
 .fc-prov__attach-row {
   display: block; font-size: 13px; text-decoration: none;
   color: rgb(var(--v-theme-accent)); padding: 2px 0;

tests/test_provenance_service.py

@@ -134,6 +134,67 @@ async def test_for_image_null_post_fields_serialize_null(db):
     assert e["post"]["attachment_count"] is None
 
 
+@pytest.mark.asyncio
+async def test_for_image_attachments_scoped_to_primary_post(db):
+    # Image linked to TWO posts; only the primary (originating) post's
+    # attachments should surface — not the other post's mega-bundle.
+    rec = await _seed_image(db)
+    a1, s1, primary = await _seed_post(db, artist_name="P1", slug="p1",
+                                       platform="patreon", ext_id="100")
+    a2, s2, bundle = await _seed_post(db, artist_name="P2", slug="p2",
+                                      platform="patreon", ext_id="200")
+    rec.primary_post_id = primary.id
+    db.add(ImageProvenance(image_record_id=rec.id, post_id=primary.id,
+                           source_id=s1.id))
+    db.add(ImageProvenance(image_record_id=rec.id, post_id=bundle.id,
+                           source_id=s2.id))
+    db.add(PostAttachment(
+        post_id=primary.id, artist_id=a1.id, sha256="p" + "0" * 63,
+        path="/images/attachments/p00/keep.zip", original_filename="keep.zip",
+        ext=".zip", mime="application/zip", size_bytes=9,
+    ))
+    db.add(PostAttachment(
+        post_id=bundle.id, artist_id=a2.id, sha256="b" + "0" * 63,
+        path="/images/attachments/b00/drop.rar", original_filename="drop.rar",
+        ext=".rar", mime="application/x-rar", size_bytes=9,
+    ))
+    await db.flush()
+
+    payload = await ProvenanceService(db).for_image(rec.id)
+    names = [a["original_filename"] for a in payload["attachments"]]
+    assert names == ["keep.zip"]
+
+
+@pytest.mark.asyncio
+async def test_for_image_attachments_fallback_to_all_posts_when_no_primary(db):
+    # No primary_post_id (older rows / filesystem imports) → preserve the
+    # aggregate-across-linked-posts behavior so attachments aren't lost.
+    rec = await _seed_image(db)
+    a1, s1, p1 = await _seed_post(db, artist_name="F1", slug="f1",
+                                  platform="patreon", ext_id="300")
+    a2, s2, p2 = await _seed_post(db, artist_name="F2", slug="f2",
+                                  platform="patreon", ext_id="400")
+    db.add(ImageProvenance(image_record_id=rec.id, post_id=p1.id,
+                           source_id=s1.id))
+    db.add(ImageProvenance(image_record_id=rec.id, post_id=p2.id,
+                           source_id=s2.id))
+    db.add(PostAttachment(
+        post_id=p1.id, artist_id=a1.id, sha256="c" + "0" * 63,
+        path="/images/attachments/c00/one.zip", original_filename="one.zip",
+        ext=".zip", mime="application/zip", size_bytes=9,
+    ))
+    db.add(PostAttachment(
+        post_id=p2.id, artist_id=a2.id, sha256="d" + "0" * 63,
+        path="/images/attachments/d00/two.zip", original_filename="two.zip",
+        ext=".zip", mime="application/zip", size_bytes=9,
+    ))
+    await db.flush()
+
+    payload = await ProvenanceService(db).for_image(rec.id)
+    names = sorted(a["original_filename"] for a in payload["attachments"])
+    assert names == ["one.zip", "two.zip"]
+
+
 @pytest.mark.asyncio
 async def test_for_post_missing_returns_none(db):
     svc = ProvenanceService(db)