feat: implement search feature for collection dropdown (#1130)

[devin-ai-integration]

This PR implements a searchable collection dropdown for the database policy configuration, addressing issue #1130.

Changes:

• Created new SearchableSelect component with client-side filtering
• Added translations for search placeholder and no-results message
• Replaced existing Select component in AddRulesModal with SearchableSelect
• Added proper form integration and error handling

Testing Status:

• ✓ Lint checks passed
• 🔄 Build verification delegated to CI pipeline

Link to Devin run: https://app.devin.ai/sessions/78b8f6da9f8541878f8f5fd27821edcc

[devin-ai-integration]

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[github-actions]

💥 laf web image built successfully for pr 2038

ghcr.io/labring/laf-web:pr-2038
docker.io/lafyun/laf-web:pr-2038

digest: sha256:e09b81560da0ccc1a90a552e50eaaac7aace2e021bf240bcd19acf4e87ed6061

[devin-ai-integration]

Closing due to inactivity.