docs: link AI nav to Overview and restructure overview page

[lyzhang0113]

What

Two changes to the AI documentation section:

Nav behavior (_data/full_tree.yml)

Make the AI sidebar entry link directly to the Overview page instead of only expanding. This matches the existing pattern used by Introduction, Hello World, and General Usage Guide — a parent node with both a path: and a childList:. The now-redundant "Overview" child is removed, so the tree is:

- name: AI
  path: /ai/overview.html
  childList:
    - name: Agent Skills
      path: /ai/agent-skills.html

Content (_articles/ai/overview.md)

• Replace the ## How to Use wrapper with one ## subheading per method: Ask AI, Agent Skills, Use with LLMs — each now has its own anchor.
• Fix typos: "buttton" → "button", "write codes" → "write code", "questions related to" → "questions about".
• Add a short description to each method.

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR improves the AI documentation section by making the AI sidebar node directly navigable to the Overview page, and by restructuring the AI Overview content into clearer, linkable sections.

Changes:

• Update the sidebar tree so the AI parent node links to /ai/overview.html (and remove the redundant Overview child entry).
• Restructure the AI Overview page into three top-level methods (Ask AI, Agent Skills, Use with LLMs) to provide clearer anchors and descriptions.
• Fix minor typos and wording for clarity.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
_data/full_tree.yml	Makes the AI nav entry clickable (links to the overview) while retaining its child navigation.
_articles/ai/overview.md	Reorganizes the overview content into three dedicated sections with improved wording and corrected typos.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.