[Docs] Add StarPerf Online Manual

[root-hbx]

Add a comprehensive documentation website for StarPerf based on mdBook.

This PR is marked as a draft for review purposes. It will be merged once all requirements are met:

• Verify Content: Texts and validate code snippets for every chapter.
• Refine Layout: Formatting and visual presentation.
• Merge: Merge this PR into the main branch.
• CI/CD Validation: Test web deployment workflow in CI/CD pipeline to ensure successful access by URL.
• Visualization Integration: We will defer this feature to a follow-up PR.

Reason for Change

The current documentation (docs/interface_convention.pdf) has several limitations:

• Difficult to navigate through long documentation
• Hard to maintain and update incrementally

This web-based solution provides:

• Web-based, searchable documentation with clear hierarchy
• Easy to maintain and extend
• Auto-CI/CD for GitHub Pages

Evaluation

Local deployment looks good, remaining for CI/CD test in our official repo.

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