chore(www): remove unused rehype plugins

[Yeom-JinHo]

Description

Remove apps/www/lib/rehype-component.ts and apps/www/lib/rehype-npm-command.ts, plus the unist type file and deps that existed only for them. Both were unregistered from the MDX pipeline in #807 (fumadocs migration) but the files were never deleted. Nothing imports them.

Changes

• Delete lib/rehype-component.ts (rehypeComponent)
• Delete lib/rehype-npm-command.ts (rehypeNpmCommand)
• Delete types/unist.ts (only imported by the two plugins above)
• Drop unist-builder, unist-util-visit, @types/unist from apps/www deps (only used by the plugins; unist-util-visit and @types/unist stay in the lockfile as transitive deps of fumadocs/rehype)

Motivation

#1018 tried to fix a bug in rehypeComponent, which surfaced that the plugin is dead code. ComponentSource has been a server component reading the registry directly since #807, so the file has had no effect on the site.

Verified with both files removed: pnpm typecheck, pnpm lint, and pnpm build pass, and prerendered docs pages still contain component source blocks.

Breaking Changes

None.

Screenshots

N/A

Checklist

• pnpm check passes locally
• pnpm build passes locally
• pnpm build:registry was run and the generated files are committed

[vercel]

@Yeom-JinHo is attempting to deploy a commit to the product-studio Team on Vercel.

A member of the Team first needs to authorize it.