feat: 更新目标帧率配置为可选，支持使用屏幕刷新率，优化渲染线程超时计算

example/test_thread/main.cpp

@@ -17,9 +17,8 @@ int main(int argc, char* argv[]) {
 	config.width                 = 800;
 	config.height                = 600;
 	config.enable_multithreading = true;
-	config.target_fps            = 60;
 	config.enable_validation     = true;
-	config.vsync                 = false;
+	config.vsync                 = true;
 
 	if (!app.initialize(config)) {
 		return -1;