fix: crash lors deconnexion LiveKit (destructuring undefined)

- LiveKitClient.emit('disconnected') envoie maintenant {reason}
- AudioBridge gere disconnected avec data optionnel (data?.reason)
- Corrige TypeError Cannot destructure property 'reason' of undefined
- Permet reload AudioBridge sans crash serveur

server/bridge/AudioBridge.js

@@ -311,7 +311,8 @@ export class AudioBridge extends EventEmitter {
       console.log('✓ LiveKit connecté');
     });
 
-    this.liveKitClient.on('disconnected', ({ reason }) => {
+    this.liveKitClient.on('disconnected', (data) => {
+      const reason = data?.reason || 'unknown';
       console.warn('⚠️  LiveKit déconnecté:', reason);
       this.stats.errors.network++;
     });