fix: resolve AI CV generator internal server errors

[YASHK-arch]

Summary

This PR resolves multiple 500 Internal Server Errors in the AI Resume & CV Generator flow. It fixes missing database columns in the Supabase migrations, corrects the GitHub session identifier passed to the GraphQL API, and makes Supabase caching non-fatal so that database errors don't prevent users from seeing their analysis.

Fixes #3125

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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

• supabase/migrations/cv_intelligence.sql: Added the missing generated_at and expires_at columns required by the API routes to both the cv_analyses and cv_generated_content tables.
• src/app/api/cv/analyze/route.ts:
  • Changed session.githubId to session.githubLogin when querying the GitHub GraphQL API, as the API requires a string username, not a numeric ID.
  • Added a resolveGitHubLogin fallback to query https://api.github.com/user for the correct username if the JWT session holds a stale or numeric login ID.
  • Wrapped the Supabase cache upsert so that database errors (like a missing table) log a warning rather than throwing a 500 status and breaking the request.
  • Relaxed development rate limits from 3 requests/hour to 100 requests/hour for easier local testing.
• src/app/api/cv/generate/route.ts:
  • Relaxed development rate limits from 5 requests/hour to 100 requests/hour.

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How to Test

1. Ensure the cv_intelligence.sql migration has been run in your Supabase instance.
2. Sign into DevTrack locally or on staging.
3. Navigate to the AI Resume Generator page and click "Analyze My GitHub Footprint".
4. Verify that the analysis completes 100% without throwing a 500 error.

Expected result: The application successfully fetches your GitHub data, classifies it, caches it in Supabase, and proceeds to the Resume Generation step without crashing.

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Screenshots / Recordings

Before :

After:

resume.mp4

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Checklist

• Linked the related issue above
• Self-reviewed my own diff
• No unnecessary console.log, debug code, or commented-out blocks
• npm run lint passes locally
• No TypeScript errors (npm run type-check)
• Added or updated tests where applicable
• Updated documentation / comments if behavior changed

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Accessibility (UI changes only)

• Keyboard navigation works correctly
• Color contrast meets WCAG AA standard
• ARIA labels / roles added where needed
• Tested on mobile / responsive layout

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Additional Context

Development rate limits were artificially restricting local testing, making debugging the API errors difficult. Production rate limits (3/hr and 5/hr) have been strictly preserved.

[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

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

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