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.

05-es6-plus/03-arrow-functions/README.md

@@ -0,0 +1,23 @@
+# 练习 3：箭头函数
+
+## 目标
+
+学会把简单函数改写成箭头函数。
+
+## 你要练什么
+
+- 箭头函数
+- 简写返回值
+- 数组映射
+
+## 任务
+
+- 把两个普通函数改成箭头函数
+- 用 `map` 和箭头函数生成课程标签
+
+## 文件
+
+- [starter.html](/Users/lijiaqing/home/wwwroot/front-end-example/05-es6-plus/03-arrow-functions/starter.html)
+- [starter.js](/Users/lijiaqing/home/wwwroot/front-end-example/05-es6-plus/03-arrow-functions/starter.js)
+- [answer.html](/Users/lijiaqing/home/wwwroot/front-end-example/05-es6-plus/03-arrow-functions/answer.html)
+- [answer.js](/Users/lijiaqing/home/wwwroot/front-end-example/05-es6-plus/03-arrow-functions/answer.js)