Major improvements:
- Add CumulativeMarkdownManager for intelligent content merging
- Implement YouTube Data API v3 integration with caption support
- Add MailChimp API integration with content cleaning
- Create single source-of-truth files that grow with updates
- Smart merging: updates existing entries with better data
- Properly combines backlog + incremental daily updates
Features:
- 179/444 YouTube videos now have captions (40.3%)
- MailChimp content cleaned of headers/footers
- All sources consolidated to single files
- Archive management with timestamped versions
- Test suite and documentation included
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
