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/02-spread-and-rest/starter.js

@@ -0,0 +1,16 @@
+const tracks = ["HTML", "CSS", "JavaScript"];
+
+const user = {
+  name: "林晨",
+  stage: "基础阶段",
+};
+
+function sumScores(...scores) {
+  // 返回总分
+}
+
+// 任务：
+// 1. 复制 tracks 并新增 "ES6+"
+// 2. 基于 user 生成一个 stage 为 "现代 JS" 的新对象
+// 3. 调用 sumScores
+// 4. 输出结果到 #output