搭建练习 (Scaffold Exercises)

创建能通过 pnpm ai-hero-cli internal lint 的练习目录结构，然后用 git commit 提交。

Create exercise directory structures that pass pnpm ai-hero-cli internal lint, then commit with git commit.

目录命名 (Directory naming)

• 章节（Sections）：exercises/ 内的 XX-section-name/（例如 01-retrieval-skill-building）

  Sections: XX-section-name/ inside exercises/ (e.g., 01-retrieval-skill-building)

• 练习（Exercises）：章节内的 XX.YY-exercise-name/（例如 01.03-retrieval-with-bm25）

  Exercises: XX.YY-exercise-name/ inside a section (e.g., 01.03-retrieval-with-bm25)

• 章节编号 = XX，练习编号 = XX.YY

  Section number = XX, exercise number = XX.YY

• 名称使用短横线命名法（小写、连字符）

  Names are dash-case (lowercase, hyphens)

练习变体 (Exercise variants)