Docs: update issue draft to avoid duplicating website content
Factors in what already exists on readthedocs/website: comparisons/
(GitHub Pages, GitBook, Cloudflare Pages, Netlify), features/reader.html,
choosing-a-platform.rst, and tools/ marketing pages. Drops duplicative
docs/ proposals (migration guides, reader tour) in favor of linking out,
and adds new website-side work items: maintainer feature pages for
Addons / PR previews / versioning, Vercel comparison, and tool marketing
pages for Docusaurus/VitePress/mdBook/Antora/MyST-MD/Zensical.
https://claude.ai/code/session_016Lf775no9EodK2n9ctz6Ss