feat(arr): serve subtitle status for title detail

Exposes per-media-file subtitles and missing wanted languages, with the
attempt reason, so #201's UI has one call per title (movies, episodes)
and one bulk call per series instead of one per episode.

.sqlx/query-f4c3eb506289667ace56da5d28c046163d5f12bd1dca53d3d6fc559f6e9ce393.json

@@ -0,0 +1,38 @@
+{
+  "db_name": "SQLite",
+  "query": "SELECT mf.id AS \"media_file_id!: i64\", e.id AS \"episode_id!: i64\"\n           FROM media_files mf\n           JOIN episodes e  ON mf.owner_kind = 'episode' AND e.id = mf.owner_id\n           JOIN seasons  se ON se.id = e.season_id\n           WHERE se.series_id = ?\n           ORDER BY mf.path",
+  "describe": {
+    "columns": [
+      {
+        "name": "media_file_id!: i64",
+        "ordinal": 0,
+        "type_info": "Integer",
+        "origin": {
+          "Table": {
+            "table": "media_files",
+            "name": "id"
+          }
+        }
+      },
+      {
+        "name": "episode_id!: i64",
+        "ordinal": 1,
+        "type_info": "Integer",
+        "origin": {
+          "Table": {
+            "table": "episodes",
+            "name": "id"
+          }
+        }
+      }
+    ],
+    "parameters": {
+      "Right": 1
+    },
+    "nullable": [
+      false,
+      false
+    ]
+  },
+  "hash": "f4c3eb506289667ace56da5d28c046163d5f12bd1dca53d3d6fc559f6e9ce393"
+}