feat(deep-scan): IR-parity port — refreshed status + counter, re-queue completed paths in deep mode, honest UX — Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

backend/app/tasks/scan.py

@@ -59,16 +59,25 @@ def scan_directory(self, triggered_by: str = "manual",
         session.flush()
         batch_id = batch.id
 
-        # Skip-set: any source_path that already has a non-failed ImportTask
-        # row. Re-running scan_directory must not re-enqueue files the
-        # importer has already handled (or is currently handling); doing so
-        # creates duplicate work and inflates the queue. Failed prior tasks
-        # are eligible for retry.
+        # Skip-set behavior splits by mode (operator-flagged 2026-05-25):
+        #
+        # quick: any non-failed prior ImportTask (active OR finished) is
+        #   skipped — quick scan only does new-file enqueue, so re-touching
+        #   already-imported files is wasted work.
+        #
+        # deep: ONLY currently-in-flight tasks (pending/queued/processing)
+        #   are skipped. Completed and skipped tasks ARE re-queued because
+        #   deep scan exists precisely to re-touch already-imported files
+        #   (refresh sidecar metadata, fill NULL phash, fill NULL artist
+        #   via Importer._deep_rederive). Matches IR's deep-scan behavior.
+        active_statuses = ["pending", "queued", "processing"]
+        if mode == "deep":
+            skip_statuses = active_statuses
+        else:
+            skip_statuses = active_statuses + ["complete", "skipped"]
         non_failed_existing = set(session.execute(
             select(ImportTask.source_path).where(
-                ImportTask.status.in_(
-                    ["pending", "queued", "processing", "complete", "skipped"]
-                ),
+                ImportTask.status.in_(skip_statuses),
             )
         ).scalars().all())