fix(subs): retry a capped language next day

A `capped` row was excluded from the work list outright, and nothing
ever moved it back, so a language that hit a daily allowance was never
attempted again. §15 says budgets drain a backlog over days, which only
holds if the cap expires.

`pending` now returns a capped row once the UTC day it was capped in has
passed — the same boundary `subtitle_budget_spend.day` uses. The day
rule is in the query rather than the caller because `limit` is a window
over the whole list: a hundred newest files capped this morning would
otherwise hold every slot and hide the older gaps until tomorrow.

Capping no longer bumps `attempts`. That counter is the failure ladder,
and a budget that refused to spend never asked a provider.

Two reporting fixes alongside, both found chasing the same bug:

- The subtitle queue dropped `last_failure` on a capped row, so all four
  limits that write `capped` rendered identically. The sentence is the
  only thing that tells a provider budget from a 429.
- A translation engine with no API key reported itself as "not compiled
  into this binary", sending the operator to rebuild an image that was
  already correct.

Co-Authored-By: Claude <noreply@anthropic.com>

.sqlx/query-1ec1a7cbb47b92e765abc3b3524824cef5ec767b42c0976c82ef7ffdc99cdf72.json

@@ -0,0 +1,12 @@
+{
+  "db_name": "SQLite",
+  "query": "INSERT INTO subtitle_attempts\n             (media_file_id, language, state, attempts, last_attempt_at, last_failure)\n         VALUES (?, ?, 'capped', 1, strftime('%Y-%m-%dT%H:%M:%fZ', 'now'), ?)\n         ON CONFLICT (media_file_id, language) DO UPDATE\n         SET state           = 'capped',\n             attempts        = MAX(subtitle_attempts.attempts, 1),\n             last_attempt_at = excluded.last_attempt_at,\n             last_failure    = excluded.last_failure,\n             updated_at      = strftime('%Y-%m-%dT%H:%M:%fZ', 'now')",
+  "describe": {
+    "columns": [],
+    "parameters": {
+      "Right": 3
+    },
+    "nullable": []
+  },
+  "hash": "1ec1a7cbb47b92e765abc3b3524824cef5ec767b42c0976c82ef7ffdc99cdf72"
+}

.sqlx/query-ba91d1e5cb04d728f2f3d2a18333897cac5bbc66e22d678a7a008e7c0efba380.json

@@ -1,6 +1,6 @@
 {
   "db_name": "SQLite",
-  "query": "SELECT a.media_file_id   AS \"media_file_id!: i64\",\n                  a.language        AS \"language!: String\",\n                  a.state           AS \"state!: SubtitleState\",\n                  a.attempts        AS \"attempts!: i64\",\n                  a.last_attempt_at,\n                  a.last_failure,\n                  f.path            AS \"media_file_path!: String\"\n           FROM   subtitle_attempts a\n           JOIN   media_files f ON f.id = a.media_file_id\n           WHERE  a.state IN ('wanted', 'failed')\n           ORDER BY f.created_at DESC, a.last_attempt_at, a.language\n           LIMIT  ?",
+  "query": "SELECT a.media_file_id   AS \"media_file_id!: i64\",\n                  a.language        AS \"language!: String\",\n                  a.state           AS \"state!: SubtitleState\",\n                  a.attempts        AS \"attempts!: i64\",\n                  a.last_attempt_at,\n                  a.last_failure,\n                  f.path            AS \"media_file_path!: String\"\n           FROM   subtitle_attempts a\n           JOIN   media_files f ON f.id = a.media_file_id\n           WHERE  (a.state IN ('wanted', 'failed')\n                   OR (a.state = 'capped'\n                       AND (a.last_attempt_at IS NULL\n                            OR a.last_attempt_at\n                               < strftime('%Y-%m-%dT00:00:00.000Z', 'now'))))\n           ORDER BY f.created_at DESC, a.last_attempt_at, a.language\n           LIMIT  ?",
   "describe": {
     "columns": [
       {
@@ -94,5 +94,5 @@
       false
     ]
   },
-  "hash": "47ad9162ba373dfbdf061898f5f148e65de261b494453804db912a919a78c2c5"
+  "hash": "ba91d1e5cb04d728f2f3d2a18333897cac5bbc66e22d678a7a008e7c0efba380"
 }