Add lychee link-check workflow and update documentation links

[FallingZYJ]

Motivation

• Ensure documentation links remain valid by adding an automated link-checker to CI.
• Update broken/legacy documentation links to point to the current docs structure.

Description

• Add a new GitHub Actions workflow at .github/workflows/lychee-link-check.yaml that runs lycheeverse/lychee-action@v2 on pull_request and push to main with options like --cache, --max-cache-age 7d, --accept 200,403,429, and outputs results to ./lychee-out.md in Markdown format using lycheeVersion: v0.23.0.
• Update README.md to adjust tutorial and API reference links to https://docs.bespokelabs.ai/bespoke-curator/data-curation-recipes and https://docs.bespokelabs.ai/bespoke-curator/api-reference.
• Make the same documentation link updates in docs/README_zh.md to keep English and Chinese docs consistent.

Testing

• No automated tests were executed as part of this PR; the new workflow is configured to run on future pull_request and push events and will report link-check results.
• The added lychee job is set to fail on broken links via fail: true and will produce a job summary and Markdown output when it runs.

---

Codex Task

[gemini-code-assist]

Caution

The consumer version of Gemini Code Assist on GitHub has been sunset. All code review activity has officially ceased.

[gemini-code-assist]

Caution

The consumer version of Gemini Code Assist on GitHub has been sunset. All code review activity has officially ceased.

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: a1c0705e6c

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[chatgpt-codex-connector]

Include local links in the checked schemes

Restricting Lychee to http and https skips relative documentation links because those are handled as file links; Lychee's --scheme documentation states that it checks only links with the specified schemes. This leaves repository-local targets unvalidated, including the currently broken docs/curator-cli.gif reference at docs/README_zh.md:42, which resolves to the nonexistent docs/docs/curator-cli.gif, so the new job can pass despite broken documentation links.

Useful? React with 👍 / 👎.