Generate annotated write-up from a presentation

You are generating a blog-style write-up from a presentation. The user will provide a presentation folder path (e.g., presentations/my-talk). That folder must contain a presentation.md file.

presentation.md format

# Talk title

- **Date:** 2026-01-15
- **Video:** https://www.youtube.com/watch?v=VIDEO_ID
- **Slides:** slides.pdf
- **Transcript:** transcript.txt

## Notes

Extra notes here