Ports the new headless-app-tanstack block and the reworked mcp-server
block onto the redesigned library.
- Register the headless app with registryItemAppend, which replaced
withClientAndDocs and already joins block docs.
- Strip a leading `~/` in getInstalledPath so the redesign's resolution,
architecture and file-tree output keep master's fix for backend files
that install outside the project's src directory.
- Give the headless app catalog metadata and a connected-agents preview
so it does not render as a second MCP server card.
- Move its block preview into the `preview:` frontmatter field the
redesign renders above the guide.
- Keep the redesign's nav spacing with master's active/hover treatment.
- Repin mcp-server's file counts: its targets moved under `~/` and it
gained a deno.lock, which the analyzer groups into the Edge Function.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
