phase29ap(p12): remove joinir legacy loop table

docs/development/current/main/phases/phase-29ae/README.md

@@ -27,6 +27,7 @@ Goal: JoinIR の最小回帰セットを SSOT として固定する。
 - Pattern7 (release adopt, VM): `phase29ao_pattern7_release_adopt_vm`
 - Pattern7: `phase29ab_pattern7_*`
 - この pack が JoinIR 回帰の唯一の integration gate（phase143_* は対象外）
+- JoinIR routing is plan/composer SSOT only (legacy loop table removed in Phase 29ap P12)
 - phase143_* は LoopBuilder 撤去 / plugin disable 固定 / LLVM exe 期待が古いので除外
 - phase286_pattern9_* は plugins disabled 経路の mismatch があるため legacy pack 側で SKIP（phase29ae pack には含めない）
 - shadow adopt tag（`[coreplan/shadow_adopt:*]`）は `filter_noise` で除去される

docs/development/current/main/phases/phase-29ap/README.md

@@ -128,6 +128,15 @@ Gate (SSOT):
   - No new logs/tags in release.
   - Gate stays green.
 
+## P12: Remove JoinIR legacy loop table ✅
+
+- Scope:
+  - Delete legacy loop table routing from JoinIR router.
+  - Remove legacy-only modules now that plan/composer is SSOT.
+- Guardrails:
+  - No change to logs or error strings.
+  - Gate stays green.
+
 ## Next (planned)
 
-- P12: Decide final removal of legacy nested loop entry (gate-first)
+- P13: Dead-code cleanup (warnings-only, no behavior change)