Split Crussell Nails.md (822 lines) into 5 focused documents:
- README.md: slimmed to 84 lines (elevator pitch + run instructions)
- Overview.md: expanded landing page with architecture diagram and quick links
- User Manual.md: 358 lines, customer-facing journeys in plain English
- Admin Manual.md: 493 lines, staff operations guide with zero technical jargon
- Technical Manual.md: 736 lines, full API reference, schema, key systems
All user/admin manuals rewritten for non-technical audiences — no API
endpoints, component names, or implementation details.