video enrichment: fix DeArrow retry (was a silent no-op)

enrichment_retry handled ryd/sponsorblock + the keyed backfills, but DeArrow (also a
youtube_video_stats backfill, keyed on dearrow_status) fell through to nothing — so the
modal's Retry button did nothing for DeArrow. Fold dearrow into the youtube_video_stats
retry branch. Regression test re-queues failed dearrow rows, leaves matched ones.

database/video_database.py

@@ -1096,9 +1096,9 @@ class VideoDatabase:
                 return cur.rowcount
             finally:
                 conn.close()
-        if service in ("ryd", "sponsorblock"):
-            col = "ryd_status" if service == "ryd" else "sb_status"
-            att = "ryd_attempted" if service == "ryd" else "sb_attempted"
+        if service in ("ryd", "sponsorblock", "dearrow"):
+            col = {"ryd": "ryd_status", "sponsorblock": "sb_status", "dearrow": "dearrow_status"}[service]
+            att = {"ryd": "ryd_attempted", "sponsorblock": "sb_attempted", "dearrow": "dearrow_attempted"}[service]
             conn = self._get_connection()
             try:
                 if scope == "item" and item_id is not None:

tests/test_video_youtube_enrichment.py

@@ -81,3 +81,21 @@ def test_proxy_instances_setting_parsing(db):
     assert ("invidious", "https://invidious.b.test") in got   # kind inferred + trailing / stripped
     assert ("piped", "https://c.test") in got
     assert all(u.startswith("http") for _, u in got)          # 'junk' dropped
+
+
+def test_dearrow_retry_requeues_failed_youtube_videos(db):
+    # Regression: enrichment_retry only handled ryd/sponsorblock, so DeArrow's
+    # Retry button was a silent no-op. It must re-queue failed dearrow rows.
+    conn = db._get_connection()
+    conn.execute("INSERT INTO youtube_video_stats (youtube_id, dearrow_status) VALUES ('a', 'not_found')")
+    conn.execute("INSERT INTO youtube_video_stats (youtube_id, dearrow_status) VALUES ('b', 'error')")
+    conn.execute("INSERT INTO youtube_video_stats (youtube_id, dearrow_status) VALUES ('c', 'ok')")
+    conn.commit(); conn.close()
+
+    n = db.enrichment_retry("dearrow", "video", scope="failed")
+    assert n == 2                                      # the not_found + error rows
+    conn = db._get_connection()
+    rows = dict(conn.execute("SELECT youtube_id, dearrow_status FROM youtube_video_stats").fetchall())
+    conn.close()
+    assert rows["a"] is None and rows["b"] is None     # re-queued
+    assert rows["c"] == "ok"                           # matched left untouched