Simplify homepage and link downloads

[macayu17]

What

Replace the default GitHub Pages instructions on the homepage with links to the existing Python archive mirror and the pyenv repository.

Why

The homepage still showed the starter template and did not link to the downloads page.

How

Update only index.html and keep the existing theme unchanged.

Part of pyenv/pyenv#2334.

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Summary by cubic

Simplifies the homepage by replacing the default GitHub Pages template with a minimal downloads view linking to the python-build mirror and the pyenv repository. Previously the homepage showed starter instructions; now it shows “pyenv downloads” with direct links. No theme changes.

• Updates only index.html; no layout, assets, or config changes.
• Verify the mirror link at /pythons/ and the repository link to https://github.com/pyenv/pyenv.
• No redirects or navigation changes beyond homepage content.

^{Written for commit ed29d94. Summary will update on new commits.}

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[cubic-dev-ai]

No issues found across 1 file

_{Re-trigger cubic}