## Summary
- `contentlayer2@0.4.6` is unmaintained and drags in a heavy, stale
dependency graph (esbuild pinned to 0.17–0.20, mdx-bundler, old
`@opentelemetry/core`) that was the recurring source of vuln bumps.
- Migrates all three apps that used it — `design-system`, `ui-library`,
`learn` — to [Velite](https://velite.js.org), preserving the generated
typed `allDocs`/`Doc` collection and the `body.code` + `useMDXComponent`
runtime via a small shared local hook.
- Same MDX pipeline (remark-gfm, remark-code-import, rehype-slug,
rehype-pretty-code w/ Shiki compat + local theme,
rehype-autolink-headings, custom
`__rawString__`/`__src__`/`__event__`/`__style__` visitors) ported 1:1
into each app's `velite.config.js`.
- `learn`'s extra frontmatter fields (`chapterNumber`, `explore`,
`courseHero`) are now backed by real Velite/Zod schema types, so the
`(doc as any)` casts in `get-next-page.ts` / `get-current-chapter.ts` /
the doc page could be dropped.
- `next.config.mjs` no longer wraps with `withContentlayer`; since
Velite has no Next.js webpack-plugin equivalent, each app's `dev` script
now runs `velite dev` and `next dev` in parallel via `npm-run-all`.
Ref:
[FE-3861](https://linear.app/supabase/issue/FE-3861/migrate-off-contentlayer2-learn-ui-library-design-system-to-shed)
## Test plan
- [x] `pnpm build:content` (Velite build) succeeds for all three apps
- [x] `pnpm typecheck` passes for all three apps
- [ ] Manual smoke test of `pnpm dev` for each app in a browser (docs
pages render, TOC, copy-button, code highlighting)
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
* **Improvements**
* Improved content generation across documentation, learning materials,
and the UI library for more consistent pages.
* Preserved MDX rendering, navigation, table of contents, course
metadata, source previews, and component examples.
* Improved consistency when displaying documentation and interactive
examples.
* Improved application loading by optimizing how interface components
are delivered.
* **Chores**
* Streamlined content compilation and development workflows across the
design system, learning area, and UI library.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
Ivan Vasilov