[Proposal] Add docs version management to GitHub Pages

[yuecideng]

Summary

Implement documentation version management in GitHub Pages to allow users to view and switch between different documentation versions for EmbodiChain.

Details

• Integrate a method (such as using mkdocs, docsify, or similar tools) to manage and display multiple versions of documentation.
• Ensure each release or major update gets a corresponding docs version.
• Update navigation and landing page to make different versions easily accessible to users.
• Add instructions in contributing guides on how to update and add new doc versions.

Benefits

• Users can reference documentation specific to their EmbodiChain version.
• Improves usability for long-term maintenance.
• Reduces confusion when features or APIs change between releases.

Acceptance Criteria

• GitHub Pages show multiple docs versions and allow easy switching.
• Documentation update process for new versions is documented.
• GitHub Pages setup remains automated and easy for maintainers.

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Labels: docs, enhancement