feat(arr): add subtitle queries

Recording a subtitle is idempotent on both keys the schema carries: the
sidecar path, and the language an embedded track satisfies, so a second
probe or a re-import converges instead of duplicating. Attempts are
upserted per (media file, language); the work list is every language that
is not satisfied, newest import first, which is the order §15 wants the
daily allowance spent in.

.sqlx/query-874079e2ed732468a1f249e6aa026753c78042e164d11eb7cc014c9500211b64.json

@@ -0,0 +1,12 @@
+{
+  "db_name": "SQLite",
+  "query": "UPDATE subtitle_files\n         SET    synced = ?, sync_rejected = ?,\n                updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now')\n         WHERE  id = ?",
+  "describe": {
+    "columns": [],
+    "parameters": {
+      "Right": 3
+    },
+    "nullable": []
+  },
+  "hash": "874079e2ed732468a1f249e6aa026753c78042e164d11eb7cc014c9500211b64"
+}