Phase 29z: RC insertion minimal（Phase 29y follow-up）
Status: Draft
Scope: Phase 29y の SSOT（RC insertion / ABI / observability）を前提に、RC insertion pass を最小動作まで進める。
Entry:
- SSOT:
docs/development/current/main/phases/phase-29y/20-RC-INSERTION-SSOT.md - 指示書:
docs/development/current/main/phases/phase-29z/P0-RC_INSERTION_MINIMAL-INSTRUCTIONS.md