refactor: replace unpublishTrack mute with setMicrophoneEnabled (Phase 1 RNNoise prep)

- syncMic now uses setMicrophoneEnabled(false/true) to mute/unmute the mic
  track in-place instead of tearing down and re-publishing via unpublishTrack().
  This eliminates WebRTC renegotiation on every mute cycle and preserves the
  Web Audio pipeline for future AudioWorklet injection (RNNoise WASM).
- Unify DmCallView mute/deafen with the primary syncMic path — removed direct
  setMicrophoneEnabled calls, added missing auto-mute/unmute on deafen toggle.
- Strip redundant applyConstraints from VoiceControls noise suppression toggle
  that was hardcoding echoCancellation:true/autoGainControl:true and fighting
  AudioManager's constraint pipeline.

packages/web/src/components/voice/VoiceControls.tsx

@@ -56,25 +56,8 @@ export function VoiceControls() {
     }
   };
 
-  const handleNoiseSuppression = async () => {
-    const room = getActiveRoom();
-    if (room) {
-      try {
-        const micPub = room.localParticipant.getTrackPublications().find(
-          p => p.source === 'microphone'
-        );
-        const mediaTrack = micPub?.track?.mediaStreamTrack;
-        if (mediaTrack) {
-          await mediaTrack.applyConstraints({
-            noiseSuppression: !noiseSuppression,
-            echoCancellation: true,
-            autoGainControl: true,
-          });
-        }
-      } catch (err) {
-        console.error('[VoiceControls] Failed to toggle noise suppression:', err);
-      }
-    }
+  const handleNoiseSuppression = () => {
+    // Store toggle triggers syncMic → AudioManager re-acquires stream with correct constraints
     toggleNoiseSuppression();
   };