fix: restore Showcase search by component name and fix result links

[jeevikar14]

Fixes #350
Problem

• The Showcase page search only filtered UI kits by name.
• Searching for a component (e.g., “button”) did not show all matching components.
  Solution
• Restored the ability to search by component name, not just UI kit name.
• Reused the search logic from the addon-catalog app for consistency.
  Testing
• Searched for “button” and verified that all relevant components from all UI kits are shown.
• Checked that clicking results opens the correct page (internal or external).
  Screenshot for validation

[netlify]

👷 Deploy request for storybook-frontpage pending review.

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🔨 Latest commit	4993caf

[netlify]

👷 Deploy request for storybook-addon-catalog pending review.

Visit the deploys page to approve it

Name	Link
🔨 Latest commit	4993caf