fix(directory-list): wire mobile View button to registry homepage link

[Santhosh1043k]

What's changed

• The mobile "View" button in apps/v4/components/directory-list.tsx had no href — clicking it did nothing.
• Fixed by using asChild on the Button component and wrapping the content in an <a> tag pointing to getHomepageUrl(registry.homepage), consistent with how the desktop title link works.

Testing

Resize browser viewport below 640px on the /directory page — the "View" button now opens the registry homepage in a new tab.

Fixes #10899

[vercel]

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[github-actions]

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