feat(registry): add @ns-ui to the registry directory

[nikolas-sapa]

Adds @ns-ui to apps/v4/registry/directory.json.

ns-ui is a public, MIT-licensed registry of 228 React components for Tailwind v4 and React 19, installable with npx shadcn add.

• Homepage: https://design.helpmarq.com
• Registry: https://design.helpmarq.com/registry.json
• Item URL: https://design.helpmarq.com/r/{name}.json (live, returns a valid registry-item.json)
• Source: https://github.com/nikolas-sapa/ns-ui (public, MIT)

It also ships a CLI (@nikolas.sapa/ns-ui) and a first-party MCP server (@nikolas.sapa/ns-ui-mcp) for browsing the catalog from an agent.

Requirements checked against the docs:

• Open source and publicly accessible
• Valid registry.json conforming to https://ui.shadcn.com/schema/registry.json
• Flat registry, no nested items
• No content property in any files entry
• validate:registries passes locally

[vercel]

@nik-sapa is attempting to deploy a commit to the shadcn-pro Team on Vercel.

A member of the Team first needs to authorize it.

[github-actions]

Can you sign the commits please? See https://docs.github.com/en/authentication/managing-commit-signature-verification/signing-commits. Thank you.

[nikolas-sapa]

Refreshed the entry: the registry is at 389 items now (was 228 when this was opened), so the description no longer undercounts. Still a single-entry diff to directory.json, and https://design.helpmarq.com/r/registry.json plus the per-item URLs are live and serving real files[].content. Happy to rebase if that helps.

[shadcn]

Thanks, added this to #11861. Closing this one so we can track it there.