Add STATE.scm checkpoint file for AI session continuity

Create comprehensive state tracking document following hyperpolymath/state.scm
format. Captures:
- Current position (Phase 1: Foundation 90% complete)
- MVP v1 roadmap (Quick Launch in 2-4 weeks)
- Known issues and blockers
- Questions pending user input
- Long-term roadmap (4 phases through search engine integration)
- Critical next actions
- Project catalog with status tracking

Author: claude