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/01-query-selectors/README.md

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+# 练习 1：获取元素
+
+## 目标
+
+学会用几种常见方式拿到页面元素。
+
+## 你要练什么
+
+- `getElementById`
+- `querySelector`
+- `querySelectorAll`
+- 元素文本读取
+
+## 任务
+
+请基于页面结构完成以下操作：
+
+- 选中主标题
+- 选中“开始学习”按钮
+- 选中全部学习卡片
+- 在控制台输出标题文字、按钮文字和卡片数量
+
+## 文件
+
+- [starter.html](/Users/lijiaqing/home/wwwroot/front-end-example/04-dom-events-async/01-query-selectors/starter.html)
+- [starter.js](/Users/lijiaqing/home/wwwroot/front-end-example/04-dom-events-async/01-query-selectors/starter.js)
+- [answer.html](/Users/lijiaqing/home/wwwroot/front-end-example/04-dom-events-async/01-query-selectors/answer.html)
+- [answer.js](/Users/lijiaqing/home/wwwroot/front-end-example/04-dom-events-async/01-query-selectors/answer.js)