Add update notice and require release build secrets

src/app_state.cpp

@@ -25,7 +25,7 @@ std::string format_download_progress(std::int64_t downloaded_size, std::int64_t
 } // namespace
 
 bool App::process_updates() {
-	bool changed = false;
+	bool changed = refresh_update_check_result();
 	while (true) {
 		auto update = td_.receive(0.0);
 		if (!update.has_value()) {