feat(Phase 3): Evolver loop 排程 + 手動觸發端點 — 合併演練閘道完工

- playbook_evolver.py: 新增 run_evolver_loop()（24h 無限迴圈）
- main.py: 掛載 run_evolver_loop asyncio.create_task
- api/v1/learning.py: POST /api/v1/learning/evolver/run（Phase 3 exit #6 演練端點）
- MASTER §8: 補錄 66c4eda AgentSession + 本次 Evolver 完整退出條件清單

ADR-083 Phase 3 — 2026-04-15 ogt + Claude Sonnet 4.6（亞太）

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/api/src/main.py

@@ -345,6 +345,15 @@ async def lifespan(_app: FastAPI) -> AsyncGenerator[None, None]:
     except Exception as e:
         logger.warning("approval_timeout_resolver_schedule_failed", error=str(e))
 
+    # ADR-083 Phase 3: Evolver Agent（每日）— Playbook 自動合併 + 低信任封存
+    # 2026-04-15 ogt + Claude Sonnet 4.6（亞太）: Phase 3 初始建立
+    try:
+        from src.services.playbook_evolver import run_evolver_loop
+        asyncio.create_task(run_evolver_loop())
+        logger.info("evolver_loop_scheduled", interval_sec=86400)
+    except Exception as e:
+        logger.warning("evolver_loop_schedule_failed", error=str(e))
+
     # ADR-083 Phase 3: 知識遺忘 Job（每日）— 30d 未引用 KB entry 標記 archived
     # 2026-04-15 ogt + Claude Sonnet 4.6（亞太）: Phase 3 初始建立
     try: