feat: add TypeScript lessons and learning panel

- Introduced a new script to check TypeScript lesson files for errors.
- Created a main TypeScript file to render lessons and their details.
- Added lesson definitions with starter and answer codes.
- Implemented a user interface for navigating and running lessons.
- Styled the application with CSS for a better user experience.
- Updated README to reflect the new TypeScript section and usage instructions.

04-dom-events-async/09-async-await-panel/README.md

@@ -0,0 +1,26 @@
+# 练习 9：async / await 面板
+
+## 目标
+
+学会用 `async` / `await` 写一个更直观的异步流程。
+
+## 你要练什么
+
+- `async`
+- `await`
+- `try...catch`
+- DOM 更新
+
+## 任务
+
+- 点击按钮后进入加载状态
+- 等待异步函数返回用户信息
+- 把结果渲染到卡片里
+- 如果失败，显示错误信息
+
+## 文件
+
+- [starter.html](/Users/lijiaqing/home/wwwroot/front-end-example/04-dom-events-async/09-async-await-panel/starter.html)
+- [starter.js](/Users/lijiaqing/home/wwwroot/front-end-example/04-dom-events-async/09-async-await-panel/starter.js)
+- [answer.html](/Users/lijiaqing/home/wwwroot/front-end-example/04-dom-events-async/09-async-await-panel/answer.html)
+- [answer.js](/Users/lijiaqing/home/wwwroot/front-end-example/04-dom-events-async/09-async-await-panel/answer.js)