feat(core,web): player queue, play events and web player controller (M3, wip)

- core: PlayQueue with shuffle and repeat, PlayAttempt counting only
  time actually played, EventBuffer with batching and backoff, uuidv7
- web: Player over HTMLAudioElement with Media Session, preload of the
  next track, expired-link refresh, local and server playback state,
  hotkeys; PlayerProvider is not wired into the shell yet
- ru/en strings and icons for the player and Collection

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/i18n/locales/ru/errors.json

@@ -61,5 +61,10 @@
   },
   "search": {
     "unavailable": "Поиск временно недоступен"
+  },
+  "playback": {
+    "link_invalid": "Ссылка устарела — обновите страницу",
+    "track_unavailable": "Трек недоступен",
+    "transcode_failed": "Не удалось подготовить трек"
   }
 }