feat: mode écoute seule pour les server audio users (Master par groupe)

Un participant serveur peut être configuré sans publier de micro —
il reçoit le mix du groupe et le sort sur un canal physique.
- ServerAudioUser: flag publish (défaut true), sendAudio no-op si false
- AudioBridgeManager: canPublish LiveKit selon flag, input_channel null si écoute
- AudioBridge: passe publish à ServerAudioUser, log adapté
- Electron UI: checkbox "Écoute seule" dans add/edit, badges 🎤/👂 dans table
- main.js IPC: persist publish + input_channel null en écoute

server/bridge/AudioBridge.js

@@ -309,6 +309,7 @@ export class AudioBridge extends EventEmitter {
         groupId: userConfig.groupId,
         inputChannel: userConfig.inputChannel,
         outputChannel: userConfig.outputChannel,
+        publish: userConfig.publish !== false,
         liveKitUrl: this.options.liveKitUrl,
         token: userConfig.token,
         sampleRate: this.options.sampleRate,
@@ -338,7 +339,10 @@ export class AudioBridge extends EventEmitter {
 
       await user.start();
       this.serverAudioUsers.set(userConfig.name, user);
-      console.log(`✓ Server audio user "${userConfig.name}" démarré (entrée canal ${userConfig.inputChannel} → sortie canal ${userConfig.outputChannel}, room: ${userConfig.groupId})`);
+      const modeStr = userConfig.publish !== false
+        ? `canal ${userConfig.inputChannel} → sortie canal ${userConfig.outputChannel ?? 'aucune'}`
+        : `écoute seule → sortie canal ${userConfig.outputChannel ?? 'aucune'}`;
+      console.log(`✓ Server audio user "${userConfig.name}" démarré (${modeStr}, room: ${userConfig.groupId})`);
     }
 
     console.log(`✓ ${this.serverAudioUsers.size} server audio user(s) initialisés`);

server/bridge/AudioBridgeManager.js

@@ -66,10 +66,12 @@ class AudioBridgeManager extends EventEmitter {
           }
         );
 
+        const publish = user.publish !== false;
+
         token.addGrant({
           room: groupId,
           roomJoin: true,
-          canPublish: true,
+          canPublish: publish,
           canSubscribe: true,
           canPublishData: true
         });
@@ -77,12 +79,14 @@ class AudioBridgeManager extends EventEmitter {
         const jwt = await token.toJwt();
 
         const outputChannel = user.output_channel ?? user.outputChannel;
+        const rawInputChannel = user.input_channel ?? user.inputChannel;
 
         serverAudioUsers.push({
           name: user.name,
           groupId,
-          inputChannel: user.input_channel ?? user.inputChannel ?? 0,
+          inputChannel: rawInputChannel !== null && rawInputChannel !== undefined ? rawInputChannel : null,
           outputChannel: outputChannel !== null && outputChannel !== undefined ? outputChannel : null,
+          publish,
           token: jwt
         });
 

server/bridge/ServerAudioUser.js

@@ -17,10 +17,13 @@ class ServerAudioUser extends EventEmitter {
     super();
 
     this.name = options.name;
-    this.inputChannel = parseInt(options.inputChannel, 10);
+    this.inputChannel = (options.inputChannel !== null && options.inputChannel !== undefined)
+      ? parseInt(options.inputChannel, 10)
+      : null;
     this.outputChannel = (options.outputChannel !== null && options.outputChannel !== undefined)
       ? parseInt(options.outputChannel, 10)
       : null;
+    this.publish = options.publish !== false; // false = écoute seule
     this.groupId = options.groupId;
     this.frameSize = options.frameSize || 960;
     this.sampleRate = options.sampleRate || 48000;
@@ -45,7 +48,8 @@ class ServerAudioUser extends EventEmitter {
 
   _setupClientEvents() {
     this.client.on('connected', () => {
-      console.log(`[ServerAudioUser:${this.name}] Connecté à room "${this.groupId}" (in:${this.inputChannel} → out:${this.outputChannel ?? 'aucune'})`);
+      const mode = this.publish ? `in:${this.inputChannel} → out:${this.outputChannel ?? 'aucune'}` : `écoute → out:${this.outputChannel ?? 'aucune'}`;
+      console.log(`[ServerAudioUser:${this.name}] Connecté à room "${this.groupId}" (${mode})`);
       this.emit('connected');
     });
 
@@ -78,7 +82,7 @@ class ServerAudioUser extends EventEmitter {
    * @param {Float32Array} float32Data - Données PCM normalisées [-1.0, 1.0]
    */
   sendAudio(float32Data) {
-    if (!this.client.isConnected) return;
+    if (!this.publish || !this.client.isConnected) return;
 
     const pcmBuffer = this._float32ToBuffer(float32Data);
     this.client.sendAudioData(pcmBuffer);