Verify generation changes and stale ACK isolation after restart

tools/chatgui/src/call_video_engine.cpp

@@ -28,7 +28,7 @@ struct CallVideoEngine::Impl {
     std::mutex lock;
     std::condition_variable wake;
     CallVideoWake rxWake;
-    CallVideoWake displayWake, guiWake;
+    CallVideoWake displayWake, guiWake{false};
     QObject* guiNotifier = nullptr;
     struct Picture { call_video_playout_frame timing; QImage image; };
     CallVideoQueue<Picture, 3> pictures;