Fix: Route Engine Overhaul for 5-Step Lifecycle

[arvarik]

Summary

Overhauls the gemstack route engine to accurately parse the 5-step lifecycle checkboxes and correctly support the cyclic Build ↔ Audit loop.

Key Changes

• Smart Audit Parsing: Fixes the infinite build loop by detecting PASS and ALL ISSUES RESOLVED inside AUDIT_FINDINGS.md.
• Deterministic Checkboxes: Regex parsing now correctly extracts Spec, Trap, Build, Audit, and Ship.
• Removes Legacy State: Fully removes the brittle [STATE: INITIALIZED] enum parsing logic.

Validation

• ruff check . and ruff format . passing.
• 345 pytest tests passing.