Enhancement — Render `NotFound` when a control panel does not exist

[VibhuGupta-dev]

Proposed Solution

Update the component to explicitly render <NotFound /> when no matching control panel is found.
This makes the behavior consistent with the rest of Volto when navigating to invalid routes.

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Benefits

• Provides clear feedback when a control panel does not exist
• Improves UX and accessibility
• Eliminates confusing blank screen behavior

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🔗 Closes

Closes #7214

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📋 Checklist

• [x] I signed and returned the Plone Contributor Agreement
• [x] I verified there aren't other open pull requests for the same change
• [x] I followed the guidelines in Contributing to Volto

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