feat(interview-questions): add GitHub CSV powered interview questions feature

[arcadep0156]

Summary

Introduces a new Interview Questions module powered by GitHub CSV data source, replacing sheet-based ingestion and enabling easier community contribution and automation.

Changes

Feature

1. Added GitHub CSV integration service
2. Implemented DevOps interview questions page
3. Added filtering and fuzzy search support
4. Added export capability for questions

UI / Components

1. Added reusable interview question card
2. Added filter and search components
3. Updated client page logic

Infrastructure

1. Updated GitHub Actions workflow to trigger rebuilds
2. Updated static export configuration for GitHub Pages
3. Improved caching strategy using service worker

Screenshots

Type/Scope

• type: feat
• scope: interview-questions, ui, ci, cache

Testing

1. Verified CSV fetch from GitHub raw URLs
2. Verified filters, search, and pagination
3. Verified static build and GitHub Pages deployment
4. Tested service worker caching behavior

Checklist

• ✅ Semantic title used
• ✅ Tests and lint checks passed
• ✅ Documentation updated
• ✅ Feature tested locally and via deployment preview (Github Actions, Github Pages also Beta Tested)

This PR enables community driven interview question contributions while keeping the platform fully static and cost-efficient.

[arcadep0156]

@LondheShubham153 Open for review and feedback. Happy to iterate based on suggestions. :)

[arcadep0156]

🚀 Updates Added

Core Changes

• ✅ Migrated interview questions from Google Sheets to GitHub CSV
• ✅ Added rate limiting (60 requests/hour) to prevent API limits
• ✅ Implemented 1-hour caching with background revalidation
• ✅ Fixed light mode text visibility in alerts
• ✅ Added error boundaries for better error handling
• ✅ Optimized Fuse.js search performance
• ✅ Updated service worker with smart caching strategy

Documentation

• ✅ Updated README.md with GitHub CSV integration details
• ✅ Updated CONTRIBUTING.md with new workflow
• ✅ Created 6 comprehensive documentation files:
  • MIGRATION_COMPLETE.md - Technical details
  • QUICK_START.md - Quick reference
  • TESTING_GUIDE.md - Testing instructions
  • WORKFLOW.md - Complete PR and deployment flow
  • ENV_FILES_EXPLAINED.md - Environment setup
  • FINAL_SUMMARY.md - Complete summary

Testing

• ✅ TypeScript compilation passing
• ✅ Production build successful
• ✅ All features tested and working

Ready for review! 🎉