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-6236e1be0e268c678271dd72be52454347da6637f0bf3ecb52dda82cddfe459a.json

@@ -0,0 +1,12 @@
+{
+  "db_name": "SQLite",
+  "query": "INSERT INTO subtitle_attempts (media_file_id, language)\n         VALUES (?, ?)\n         ON CONFLICT (media_file_id, language) DO NOTHING",
+  "describe": {
+    "columns": [],
+    "parameters": {
+      "Right": 2
+    },
+    "nullable": []
+  },
+  "hash": "6236e1be0e268c678271dd72be52454347da6637f0bf3ecb52dda82cddfe459a"
+}