fix: souscription manuelle aux tracks audio des participants

Problème : RoomEvent.TrackSubscribed ne se déclenchait jamais avec @livekit/rtc-node
Solution :
- Itération manuelle sur participant.trackPublications quand participant se connecte
- Création AudioStream immédiate si track audio disponible
- Factorisation code dans _handleAudioTrack()

Cela devrait permettre de recevoir l'audio des clients PWA.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

server/bridge/LiveKitClient.js

@@ -136,8 +136,19 @@ export class LiveKitClient extends EventEmitter {
     });
 
     // Participants
-    this.room.on(RoomEvent.ParticipantConnected, (participant) => {
+    this.room.on(RoomEvent.ParticipantConnected, async (participant) => {
       console.log(`➕ Participant connecté: ${participant.identity}`);
+
+      // Parcourir les tracks publiés par ce participant et s'y abonner manuellement
+      for (const [trackSid, publication] of participant.trackPublications) {
+        console.log(`  📝 Track disponible: ${publication.kind} (${trackSid}), muted: ${publication.muted}`);
+
+        if (publication.kind === 'audio' && publication.track) {
+          console.log(`  ⚡ Souscription manuelle au track audio ${trackSid}...`);
+          await this._handleAudioTrack(publication.track, publication, participant);
+        }
+      }
+
       this.emit('participantConnected', participant);
     });
 
@@ -152,11 +163,30 @@ export class LiveKitClient extends EventEmitter {
       console.log(`📢 Track publié par ${participant.identity}: ${publication.kind} (${publication.sid}), muted: ${publication.muted}`);
     });
 
-    this.room.on(RoomEvent.TrackSubscribed, (track, publication, participant) => {
+    this.room.on(RoomEvent.TrackSubscribed, async (track, publication, participant) => {
       console.log(`🎵 Track souscrit de ${participant.identity}: ${track.kind} (${publication.sid})`);
 
       if (track.kind === 'audio') {
-        console.log(`🎵 Track AUDIO souscrit de ${participant.identity}, création AudioStream...`);
+        console.log(`🎵 Track AUDIO souscrit de ${participant.identity} (événement TrackSubscribed)`);
+        await this._handleAudioTrack(track, publication, participant);
+      }
+    });
+
+    this.room.on(RoomEvent.TrackUnsubscribed, (track, publication, participant) => {
+      if (track.kind === 'audio') {
+        console.log(`🔇 Track audio désouscrit de ${participant.identity}`);
+        this.remoteParticipants.delete(participant.sid);
+        this.emit('audioTrackUnsubscribed', { track, participant });
+      }
+    });
+  }
+
+  /**
+   * Gère un track audio (création AudioStream et lecture)
+   * @private
+   */
+  async _handleAudioTrack(track, publication, participant) {
+    console.log(`🎧 Création AudioStream pour ${participant.identity}...`);
 
     // Création d'un AudioStream pour recevoir les données PCM
     const stream = new AudioStream(
@@ -177,16 +207,6 @@ export class LiveKitClient extends EventEmitter {
 
     this.emit('audioTrackSubscribed', { track, participant });
   }
-    });
-
-    this.room.on(RoomEvent.TrackUnsubscribed, (track, publication, participant) => {
-      if (track.kind === 'audio') {
-        console.log(`🔇 Track audio désouscrit de ${participant.identity}`);
-        this.remoteParticipants.delete(participant.sid);
-        this.emit('audioTrackUnsubscribed', { track, participant });
-      }
-    });
-  }
 
   /**
    * Démarre la réception audio d'un participant