Audit crate boundaries and responsibilities

[avrabe]

Goal

Document current crate structure and identify issues.

Tasks

• Document current responsibility of each crate
• Identify overlaps (synth-synthesis vs synth-opt)
• Identify gaps (missing integration layer?)
• Propose consolidation plan
• Create crate dependency diagram

Questions to Answer

1. What's the difference between synth-synthesis and synth-opt?
2. Should synth-codegen and synth-backend be merged?
3. Is synth-regalloc needed as separate crate?
4. What's the actual vs ideal crate structure?

Deliverable

• Document: docs/architecture/CRATE_STRUCTURE.md
• Clear responsibility matrix
• Dependency diagram
• Refactoring proposal

Acceptance Criteria

• ✅ Complete crate audit done
• ✅ Issues identified and documented
• ✅ Refactoring plan proposed