fix(metrics): enforce commit count ranking and date window filtering …

[Nareshkumawat-star]

Summary

Ensures the TopRepos.tsx widget and /api/metrics/repos API route accurately rank repositories based on author commit count within the selected time range (7d / 30d / 90d). Repositories are queried via GitHub's Commit Search API (author:{login} author-date:>={since}), tallied per repo, cached via Supabase/Redis TTL cache, and rendered with commit count badges and relative progress bars.

Closes #3248

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Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that changes existing behavior)
• 📝 Documentation update
• ♻️ Refactor / code cleanup (no functional change)
• ⚡ Performance improvement
• 🔒 Security fix
• 🧪 Tests only

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What Changed

• src/app/api/metrics/repos/route.ts: Uses GitHub Commit Search API (author:login author-date:>=sinceStr) to fetch user commits within the selected date window (days). Groups commits by repository, tallies counts, sorts descending by user commit count, and fetches top repository language breakdowns concurrently.
• src/components/TopRepos.tsx: Renders repositories ordered by commit count with commit badges ({repo.commits} commits), relative bar widths, search filtering, pinning, bookmarking, and time-range selection (7d, 30d, 90d).

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How to Test

1. Navigate to the DevTrack dashboard and scroll to the Top Repositories widget.
2. Select different time ranges (Last 7d, Last 30d, Last 90d).
3. Verify that repositories are ordered by commit count within the selected window and display the correct commit badge count next to each repository.

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Checklist

• Self-reviewed my own diff
• No unnecessary console.log or debug code
• Commit count ranking logic verified
• Cached via withMetricsCache to prevent rate limit issues

[github-actions]

GSSoC Label Checklist 🏷️

@Priyanshu-byte-coder — please apply the appropriate labels before merging:

Difficulty (pick one):

• level:beginner — 20 pts
• level:intermediate — 35 pts
• level:advanced — 55 pts
• level:critical — 80 pts

Quality (optional):

• quality:clean — ×1.2 multiplier
• quality:exceptional — ×1.5 multiplier

Validation (required to score):

• gssoc:approved — counts for points
• gssoc:invalid / gssoc:spam / gssoc:ai-slop — does not score

Type labels (type:*) are auto-detected from files and title. Review and adjust if needed.
Points formula: (difficulty × quality_multiplier) + type_bonus

[Nareshkumawat-star]

Hi @Priyanshu-byte-coder kindly review and merge it