Add RSS feed of releases to the public server

[passcod]

What

Adds an RSS 2.0 feed of releases to the public server, served at GET /versions/rss.

Each feed item corresponds to a published, ready-to-serve version — the same set the existing /versions JSON listing and homepage expose (published, not covered by a known-issue range), ordered newest first. The changelog markdown is rendered to HTML for the item body, mirroring the per-version HTML page.

Details

• Endpoint: GET /versions/rss, mounted as a plain (non-OpenAPI) route in versions::routes() alongside the other HTML/streaming routes, gated behind the ui feature (it reuses parse_markdown). Content type application/rss+xml; charset=utf-8.
• Feed generation: uses the rss crate (added to the workspace and to public-server as an optional dep under the ui feature) rather than hand-rolling XML.
• Item shape: title Canopy <version>, link/guid pointing at the version's page, pubDate from created_at (RFC 2822, UTC), and the rendered changelog as the description.
• Absolute links: derived from PUBLIC_URL when configured, otherwise reconstructed from the request's X-Forwarded-Proto and Host headers so local and test runs still emit well-formed links.
• Discoverability: adds an <link rel="alternate" type="application/rss+xml"> autodiscovery tag to the versions homepage.

Tests

Adds two integration tests in crates/public-server/tests/it/versions.rs:

• releases_rss_feed — asserts the content type, RSS structure, newest-first ordering, exclusion of drafts, and that changelog markdown is rendered.
• releases_rss_feed_excludes_known_issue_versions — asserts versions covered by a known-issue range are hidden, matching /versions.

Both pass. The route is intentionally excluded from the OpenAPI spec (like the existing HTML/download routes), so no openapi.json regeneration is needed.

🤖 Generated with Claude Code

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Generated by Claude Code