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/en/common.json

@@ -89,7 +89,10 @@
     "session_current": "This device",
     "session_last_used": "Active: {{date}}",
     "session_end": "Sign out",
-    "logout_all": "Sign out everywhere"
+    "logout_all": "Sign out everywhere",
+    "wave_variant": "Wave style",
+    "wave_orb": "Orb",
+    "wave_liquid": "Liquid"
   },
   "form": {
     "show_password": "Show password",
@@ -155,5 +158,31 @@
     "empty_dislikes": "Disliked tracks stay out of the wave. None so far",
     "play_all": "Play all",
     "more": "Show more"
+  },
+  "wave": {
+    "title": "My Wave",
+    "for_you": "Tuned to your taste",
+    "start": "Start My Wave",
+    "pause": "Pause My Wave",
+    "activity_label": "Activity",
+    "mood_label": "Mood",
+    "reset": "Reset",
+    "empty": "Nothing to suggest yet — the library is empty",
+    "fallback": "Recommendations are simplified for now",
+    "activities": {
+      "running": "Running",
+      "workout": "Workout",
+      "waking_up": "Waking up",
+      "focus": "Focus",
+      "commute": "Commute",
+      "chill": "Chilling",
+      "sleep": "Falling asleep"
+    },
+    "moods": {
+      "energetic": "Energetic",
+      "happy": "Happy",
+      "calm": "Calm",
+      "sad": "Sad"
+    }
   }
 }