Create STATE.scm project documentation file (#2)

Implements Guile Scheme state tracking per hyperpolymath/state.scm
format:
- Project metadata and user context
- Current focus (planning phase) with blockers
- Project catalog with completion tracking
- Route to MVP v1 with phased roadmap
- Open issues and pending questions for user
- Long-term architectural roadmap
- Query interface functions

Co-authored-by: Claude <noreply@anthropic.com>

Author: hyperpolymath