Add an initial TypeScript track for the learning materials

[chen893]

Summary

This draft PR adds an initial TypeScript track alongside the existing Python-based learning materials.

The goal is to make the repository easier to follow for readers who primarily work in the Node.js / TypeScript ecosystem, while keeping the current Python path intact.

Included in this PR

• a new agents-ts/ directory with TypeScript implementations for s01 through s12
• README updates to mention the TypeScript track
• documentation updates in docs/en, docs/zh, and docs/ja to include TypeScript-specific snippets/content where relevant
• docs site updates so the main learning pages can be browsed by language (python / s)
• content extraction and generated data updates so TypeScript sources are indexed in the site
• a small test addition around extraction / learning-path routing behavior

Intent

This PR is meant to be additive rather than a replacement of the existing Python materials.

I tried to keep the TypeScript structure aligned with the current session progression so readers can compare the two tracks more easily.

Why this is a draft

This change touches examples, docs, generated data, and the docs site together, so I wanted to open it as a draft first to validate direction and scope before asking for a full review.

Feedback I’d especially appreciate

• whether an additional TypeScript track fits the intended scope of the project
• whether the current structure (agents-ts + site integration) is acceptable
• whether you’d prefer this to be split into smaller PRs before formal review

[vercel]

@chen893 is attempting to deploy a commit to the crazyboym's projects Team on Vercel.

A member of the Team first needs to authorize it.

[chen893]

I’ve also deployed a preview to make the docs/site changes easier to review:

Preview: https://learn-claude-code-three.vercel.app/en/

Useful paths to check:

• https://learn-claude-code-three.vercel.app/en/python/s01/
• https://learn-claude-code-three.vercel.app/en/ts/s01/
• https://learn-claude-code-three.vercel.app/en/ts/s10/diff/
• https://learn-claude-code-three.vercel.app/zh/ts/s03/