fix(cleanup): library scans survive navigation, reconnect on return

The transparency / single-color audit cards held the run + poll timer in
local component state, so navigating away destroyed both and onMounted never
reconnected — the Celery scan kept running and writing LibraryAuditRun, but
the UI forgot it. Now each card, on mount, fetches its rule's latest run
(GET /api/cleanup/audit?rule=<rule>&limit=1) and rehydrates: shows progress +
resumes polling if still running, or shows the completed result (ready/applied/
error) so the operator can act on it after returning. Adds the ?rule= filter
to the audit-history endpoint + cleanup store latestAuditForRule().

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

backend/app/api/cleanup.py

@@ -154,12 +154,15 @@ async def audit_history():
         limit = min(int(request.args.get("limit", "20")), 100)
     except ValueError:
         return _bad("invalid_limit")
+    # Optional rule filter so a card can reconnect to ITS latest run on mount
+    # (?rule=transparency&limit=1) — the audit survives navigation; the UI
+    # rehydrates from this rather than losing the in-flight scan.
+    rule = request.args.get("rule") or None
     async with get_session() as session:
-        rows = (await session.execute(
-            select(LibraryAuditRun)
-            .order_by(LibraryAuditRun.id.desc())
-            .limit(limit)
-        )).scalars().all()
+        stmt = select(LibraryAuditRun).order_by(LibraryAuditRun.id.desc())
+        if rule is not None:
+            stmt = stmt.where(LibraryAuditRun.rule == rule)
+        rows = (await session.execute(stmt.limit(limit))).scalars().all()
         return jsonify({"runs": [_serialize_audit_run(r) for r in rows]})
 
 

frontend/src/components/cleanup/SingleColorAuditCard.vue

@@ -112,6 +112,16 @@ onMounted(async () => {
   await store.loadDefaults()
   threshold.value = store.defaults.single_color_threshold
   tolerance.value = store.defaults.single_color_tolerance
+  // Reconnect to this rule's latest run so a scan started before navigating
+  // away keeps showing progress / its result on return (the scan itself runs
+  // backend-side regardless).
+  try {
+    const latest = await store.latestAuditForRule('single_color')
+    if (latest) {
+      audit.value = latest
+      if (latest.status === 'running') startPoll(latest.id)
+    }
+  } catch { /* non-fatal — card still works for a fresh scan */ }
 })
 
 onUnmounted(() => stopPoll())

frontend/src/components/cleanup/TransparencyAuditCard.vue

@@ -97,6 +97,16 @@ let pollTimer = null
 onMounted(async () => {
   await store.loadDefaults()
   threshold.value = store.defaults.transparency_threshold
+  // Reconnect to this rule's latest run so a scan started before navigating
+  // away keeps showing progress / its result on return (the scan itself runs
+  // backend-side regardless).
+  try {
+    const latest = await store.latestAuditForRule('transparency')
+    if (latest) {
+      audit.value = latest
+      if (latest.status === 'running') startPoll(latest.id)
+    }
+  } catch { /* non-fatal — card still works for a fresh scan */ }
 })
 
 onUnmounted(() => stopPoll())

frontend/src/stores/cleanup.js

@@ -55,6 +55,14 @@ export const useCleanupStore = defineStore('cleanup', () => {
     return body.runs
   }
 
+  // The most recent audit run for a given rule, or null. Cards call this on
+  // mount to reconnect to a scan that's still running (or to show the last
+  // completed result) after the user navigates away and back.
+  async function latestAuditForRule(rule) {
+    const body = await api.get('/api/cleanup/audit', { params: { rule, limit: 1 } })
+    return (body.runs && body.runs[0]) || null
+  }
+
   async function applyAudit(id, confirm) {
     return await api.post(`/api/cleanup/audit/${id}/apply`, { body: { confirm } })
   }
@@ -67,6 +75,6 @@ export const useCleanupStore = defineStore('cleanup', () => {
     defaults, recentRuns,
     loadDefaults,
     previewMinDim, deleteMinDim,
-    startAudit, getAudit, loadHistory, applyAudit, cancelAudit,
+    startAudit, getAudit, loadHistory, latestAuditForRule, applyAudit, cancelAudit,
   }
 })

tests/test_api_cleanup.py

@@ -155,6 +155,27 @@ async def test_audit_history_returns_recent_runs(client, db):
     assert len(body["runs"]) >= 3
 
 
+@pytest.mark.asyncio
+async def test_audit_history_filters_by_rule(client, db):
+    db.add(LibraryAuditRun(
+        rule="transparency", params={"threshold": 0.9},
+        status="applied", matched_ids=[], finished_at=datetime.now(UTC),
+    ))
+    db.add(LibraryAuditRun(
+        rule="single_color", params={"threshold": 0.95, "tolerance": 30},
+        status="ready", matched_count=2, matched_ids=[1, 2],
+        finished_at=datetime.now(UTC),
+    ))
+    await db.commit()
+    # ?rule=&limit=1 → just THIS rule's latest run (the card-reconnect query).
+    resp = await client.get("/api/cleanup/audit?rule=single_color&limit=1")
+    assert resp.status_code == 200
+    runs = (await resp.get_json())["runs"]
+    assert len(runs) == 1
+    assert runs[0]["rule"] == "single_color"
+    assert runs[0]["matched_count"] == 2
+
+
 @pytest.mark.asyncio
 async def test_audit_apply_with_token_deletes(client, db, tmp_path):
     rec = await _seed_image(db, tmp_path, w=100, h=100, name="apply.png")