Fix event group reference in app_main for shutdown handling

main/main.cpp

@@ -90,7 +90,7 @@ void app_main(void) {
     touch_handler->start_event_loop();
     // wait for shutdown signal
     EventBits_t bits = xEventGroupWaitBits(
-      system_event_group,
+      system_lifecycle_event_group,
       SYSTEM_SHUTDOWN_BIT | SYSTEM_RESTART_BIT,
       // do not clear on exit, require explicit reset
       pdFALSE,