Section Builder AI Improvements

Suggested improvements to the AI tool to build sections:

1. It only edits rather than rebuilds the whole section (this would make a huge difference as currently it can make things worse) Split into own task

2. Ability to reference an existing section from a list? Split into own task

3. Ensure it can get context from the whole library? Split into own task

4. Make sure it preserves comments when it’s editing section code. Split into own task

5. Add image/screenshot option? Split into own task

6. Use Skill MD files