feat(web): My Wave button, mood picker and endless wave playback (M4)

- WaveButton: TypeScript port of the prototype's canvas animation
  (orb and liquid), breathing at rest, pulsing to the track's BPM and
  energy in the cover palette, following the cursor, pressing with a
  spring; reduced motion and hidden tabs slow or stop it
- home: the wave in the centre with activity and mood chips; changing
  them while playing rebuilds the upcoming tracks without stopping
- player wave mode: asks for the next batch when two tracks are left,
  sends complete / skip / early skip / like / dislike as feedback and
  refreshes the queue right after a reaction or an early skip
- tracks expose bpm, energy and loudness once analysed; library page
  shows analysis progress and 7-day wave metrics; wave style setting

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

packages/i18n/locales/ru/errors.json

@@ -45,7 +45,9 @@
     "name_invalid": "Название — от 1 до {{max}} символов",
     "scan_interval_invalid": "Интервал — не меньше {{min}} минут",
     "source_type_invalid": "Неизвестный тип хранилища",
-    "query_empty": "Введите запрос"
+    "query_empty": "Введите запрос",
+    "wave_activity_invalid": "Неизвестное занятие",
+    "wave_mood_invalid": "Неизвестное настроение"
   },
   "users": {
     "not_found": "Пользователь не найден",
@@ -66,5 +68,8 @@
     "link_invalid": "Ссылка устарела — обновите страницу",
     "track_unavailable": "Трек недоступен",
     "transcode_failed": "Не удалось подготовить трек"
+  },
+  "wave": {
+    "session_not_found": "Сессия волны завершена"
   }
 }