docs(phase29ao): add coreloop exitmap composition ssot (p20)

docs/development/current/main/10-Now.md

@@ -2,12 +2,16 @@
 
 ## Current Focus: Phase 29ao（CorePlan composition）
 
-Next: Phase 29ao P20（CoreLoop ExitMap composition docs-first）
-指示書: `docs/development/current/main/phases/phase-29ao/P20-CORELOOP-EXITMAP-COMPOSITION-SSOT-INSTRUCTIONS.md`
+Next: Phase 29ao P21（TBD）
+指示書: TBD
 運用ルール: integration filter で phase143_* は回さない（JoinIR 回帰は phase29ae pack のみ）
 運用ルール: phase286_pattern9_* は legacy pack (SKIP) を使う
 移行道筋 SSOT: `docs/development/current/main/design/coreplan-migration-roadmap-ssot.md`
 
+**2025-12-30: Phase 29ao P20 完了** ✅
+- 目的: CoreLoop の ExitMap/Cleanup/ValueJoin 合成規約を SSOT 化（docs-only）
+- 変更: `docs/development/current/main/design/coreloop-exitmap-composition-ssot.md` / `docs/development/current/main/design/planfrag-ssot-registry.md` / `docs/development/current/main/phases/phase-29ao/README.md` / `docs/development/current/main/10-Now.md` / `docs/development/current/main/30-Backlog.md` / `CURRENT_TASK.md`
+
 **2025-12-30: Phase 29ao P19 完了** ✅
 - 目的: regression gate に Pattern1 strict/dev shadow adopt を含め、回帰で必ず踏む（SSOT化）
 - 変更: `tools/smokes/v2/profiles/integration/joinir/phase29ao_pattern1_strict_shadow_vm.sh` / `tools/smokes/v2/profiles/integration/joinir/phase29ae_regression_pack_vm.sh` / `docs/development/current/main/phases/phase-29ae/README.md`