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/08-promise-and-render/README.md

@@ -0,0 +1,26 @@
+# 练习 8：Promise 和渲染
+
+## 目标
+
+学会在 Promise 完成后把结果渲染到页面。
+
+## 你要练什么
+
+- Promise
+- `.then()`
+- `catch()`
+- loading 状态
+
+## 任务
+
+- 点击按钮后显示“加载中”
+- 等待 Promise 返回数据
+- 把课程名称渲染到列表
+- 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/08-promise-and-render/starter.html)
+- [starter.js](/Users/lijiaqing/home/wwwroot/front-end-example/04-dom-events-async/08-promise-and-render/starter.js)
+- [answer.html](/Users/lijiaqing/home/wwwroot/front-end-example/04-dom-events-async/08-promise-and-render/answer.html)
+- [answer.js](/Users/lijiaqing/home/wwwroot/front-end-example/04-dom-events-async/08-promise-and-render/answer.js)