feat(camera): handle camera-track end with branched toast (unplug vs permission revoke)

LocalTrackPublished registers a one-shot onended on the camera track's
MediaStreamTrack. The handler:
  - skips when consumeIntentionalCameraOff() flag is set (user-initiated)
  - re-probes getUserMedia to distinguish NotAllowedError (permission
    revoked) from NotFoundError (disconnected) from other errors
  - tears down camera state via the unified path

Also reset _intentionalCameraOff in voiceActions if setCameraEnabled(false)
rejects, so a failed disable doesn't poison the next genuine unplug.

packages/web/src/utils/voiceActions.ts

@@ -80,7 +80,14 @@ export async function handleCameraAction(): Promise<void> {
       // Mark this disable as intentional so the track-`ended` handler skips
       // its unplug/permission-revoke probe + toast.
       markIntentionalCameraOff();
-      await room.localParticipant.setCameraEnabled(false);
+      try {
+        await room.localParticipant.setCameraEnabled(false);
+      } catch (err) {
+        // Disable rejected — consume the flag so it doesn't poison the
+        // next genuine unplug. Re-throw to the outer catch for logging.
+        consumeIntentionalCameraOff();
+        throw err;
+      }
     }
     useVoiceStore.getState().toggleCamera();
     broadcastVoiceStatus();