fix: add missing utils.ts (cn utility)

[Kamilbenkirane]

Summary

• Adds missing src/lib/utils.ts file that provides the cn utility for classnames
• This fixes the build error: Cannot find module '@/lib/utils'

Test plan

• File exists and exports cn function
• Build succeeds after merge

[claude]

PR Review: Add missing utils.ts (cn utility)

✅ Summary

This PR adds the missing src/lib/utils.ts file that provides the cn utility function for merging Tailwind CSS classnames. This fixes the build error caused by imports from @/lib/utils in existing components.

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📋 Code Quality & Best Practices

Strengths:

• ✅ Standard implementation pattern for the cn utility function
• ✅ Proper TypeScript typing with ClassValue from clsx
• ✅ Dependencies (clsx and tailwind-merge) are already present in package.json
• ✅ Follows common shadcn/ui convention for utility organization

Issues to address:

1. Missing newline at end of file (Line 6)

   • The file should end with a newline character per standard conventions
   • Most linters and formatters expect this

2. Redundant local utility in InstallSelector.tsx

   • src/components/InstallSelector.tsx:8-10 defines a local classNames function
   • This should be removed and replaced with the cn import since it's now available
   • The local function is less robust (doesn't handle Tailwind class merging)

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🐛 Potential Bugs

Minor issue:

• The InstallSelector.tsx component uses both the imported cn (line 5) and a local classNames function (lines 8-10, used on lines 83, 106, 114)
• This creates confusion and the local classNames doesn't provide the same Tailwind merging benefits
• Recommendation: Update all classNames() calls to use cn() instead

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⚡ Performance Considerations

• ✅ No performance concerns
• The cn utility is lightweight and only called during render
• Both clsx and tailwind-merge are well-optimized libraries

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🔒 Security Concerns

• ✅ No security issues identified
• The utility function only manipulates strings for CSS classes
• Dependencies are legitimate, widely-used packages

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🧪 Test Coverage

Current state:

• ⚠️ No tests included for the utility function
• Test plan shows "Build succeeds after merge" is unchecked

Recommendations:

1. While unit tests for cn aren't critical (it's a simple wrapper), verifying the build passes is important
2. Consider running the build locally before merging: npm run build or bun run build
3. The existing components using this utility (SidebarSearch, InstallSelector) serve as integration tests

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📝 Action Items

Before merging:

1. Add newline at end of src/lib/utils.ts
2. Run bun run format to ensure consistent formatting
3. Verify build succeeds: bun run build

Follow-up (can be separate PR):

1. Remove the local classNames function from InstallSelector.tsx:8-10
2. Replace all classNames() calls with cn() in that file

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🎯 Overall Assessment

Verdict: ✅ Approve with minor fixes

This is a necessary fix that resolves a build-blocking issue. The implementation is correct and follows standard patterns. The main concerns are cosmetic (missing newline) and can be addressed quickly. The redundant local utility in InstallSelector.tsx should be cleaned up but doesn't block this PR.

Great work fixing this! 🚀