feat: add changelog support to the template

[martyy-code]

Problem statement

The template currently has no dedicated place for release notes. Adopters who want a public changelog either:

• inline it in the docs (pollutes the documentation tree),
• point users at GitHub Releases (loses branding and styling),
• or build a separate page from scratch (duplicates work the template should ship).

A common need for a docs site is a versioned changelog that follows the Keep a Changelog convention.

Proposed solution

Add a /changelog route group that:

• Lives at /changelog (sibling of /docs and /blog)
• Reads content from content/changelog/ (parallel to content/docs/)
• Uses a second Fumadocs loader() source collection for releases
• Frontmatter: version (semver), date (ISO), optional title
• Body follows Keep a Changelog categories: Added, Changed, Fixed, Deprecated, Removed, Security — rendered as styled sections
• Index page lists releases, newest first, with version + date + a one-line summary
• Individual pages at /changelog/<version> (e.g. /changelog/v1-2-0)
• Latest release prominently surfaced on the home page or in the docs sidebar
• Generates an Atom/RSS feed at /changelog/feed.xml via a dynamic route handler so users can subscribe to release notifications (see docs/internal/learnings/fumadocs/rss.md)
• Optional: /llms-full.txt extended to include the changelog

Keep a Changelog rendering

The Added/Changed/Fixed/etc. sections are rendered via a custom MDX component (e.g. src/components/change-section.tsx) that maps each ## Added heading to a styled block (similar in spirit to Fumadocs' <Callout>). The component receives the section type as a prop and renders with the appropriate color/icon.

Two example releases should ship in the template (content/changelog/v1.0.0.mdx, v0.9.0.mdx) to demonstrate the schema and Keep a Changelog rendering.

Acceptance criteria

• /changelog route renders a reverse-chronological list of releases
• /changelog/<version> renders a single release with Keep a Changelog sections
• Frontmatter schema (version, date, optional title) is validated by source.config.ts
• Latest release is surfaced somewhere visible (home or sidebar)
• Two example releases ship in the template with realistic entries
• README.md documents the changelog conventions and how to add a new release
• All existing CI checks (Lint, Type Check, Build) still pass
• No regressions on the docs section
• (Recommended) Atom/RSS feed at /changelog/feed.xml — same feed-based pattern as /blog/feed.xml (see RSS learning doc). Register in metadata.alternates.types.

Alternatives considered

• Auto-generate from git log in CI. Rejected — produces noisy, inconsistent output, and conflates commit history with user-facing release notes.
• Pull from the GitHub Releases API only. Rejected — couples the template to GitHub and loses theming, layout control, and offline builds.
• Single-page flat changelog (one long page, no per-release routing). Rejected — does not scale past a handful of releases and provides no per-version URL for linking.
• Fold changelog entries into the blog (post type = "release"). Rejected — conflates concerns (release notes have a strict format and versioning; blog posts are free-form).

Risks

• Another content collection means a third loader() call and a third source tree in the navigation. Layout decisions (where to surface the latest release) need a UX pass.
• If the blog and changelog land together, the home/sidebar layout has to accommodate three entry points (docs, blog, changelog) without becoming cluttered.
• If i18n is also adopted (see feat(docs): add internationalization (i18n) support #10), the changelog content tree must follow the same parser choice as docs and blog. Document this in the migration guide.
• RSS feed sort order — releases must sort by version descending (semver), not by date. Custom comparator required.

Related

• Keep a Changelog: https://keepachangelog.com
• Semantic Versioning: https://semver.org
• Fumadocs source API: https://fumadocs.dev/docs/headless/source-api
• Sibling issue: feat: add blog support to the template #1 (blog support) — shares the multi-collection pattern and the RSS feed pattern
• Sibling issue: feat(docs): add internationalization (i18n) support #10 (i18n) — changelog must follow the same parser
• Reference learning: docs/internal/learnings/fumadocs/markdown.md (Callout component for section rendering)
• Reference learning: docs/internal/learnings/fumadocs/rss.md (RSS feed pattern with feed package)