Optimize duplicate breakpoint detection and fix useEffect dependencies

[smartlabsAT]

Summary

• Optimize duplicate breakpoint detection from O(n²) to O(n) complexity
• Fix missing useEffect dependency to prevent stale closures
• Maintain existing functionality with improved performance

Changes Made

🚀 Performance Optimization

Before: Used filter with findIndex causing O(n²) complexity

const duplicates = sortedBreakpoints.filter(
  ([, value], index) => sortedBreakpoints.findIndex(([, v]) => v === value) !== index
);

After: Use Set-based approach for O(n) complexity

const seenValues = new Set<number>();
const duplicates: Array<[Breakpoint, number]> = [];

for (const entry of sortedBreakpoints) {
  const [, value] = entry;
  if (seenValues.has(value)) {
    duplicates.push(entry);
  } else {
    seenValues.add(value);
  }
}

🔧 Bug Fix

Before: Missing dependency in useEffect

}, [sortedBreakpoints]);

After: Complete dependency array

}, [sortedBreakpoints, shouldLog]);

Benefits

• ✅ Performance: Significantly better performance with larger breakpoint arrays
• ✅ Correctness: Prevents stale closure issues when shouldLog changes
• ✅ Maintainability: Cleaner, more explicit code
• ✅ Testing: All existing tests continue to pass

Quality Checks

• ✅ All tests pass (5/5)
• ✅ ESLint validation passed
• ✅ TypeScript compilation successful
• ✅ Pre-commit hooks passed (lint, typecheck, build, test)

Test plan

• Existing functionality verified through test suite
• Performance improvement confirmed (O(n) vs O(n²))
• No regressions in duplicate detection logic
• useEffect dependency fix prevents potential closure issues

Fixes #4