fix(ai-ops): 修正 _init_autoheal_tables 建表順序 (Playbook 先於 Incident FK)

incidents.playbook_id → FK → playbooks.id
建表必須先 Playbook 再 Incident，否則 psycopg2 報 UndefinedTable

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

database/manager.py

@@ -127,7 +127,7 @@ class DatabaseManager:
             inspector = sa_inspect(self.engine)
             existing_tables = inspector.get_table_names()
 
-            for model in [Incident, Playbook, HealLog]:
+            for model in [Playbook, Incident, HealLog]:
                 if model.__tablename__ not in existing_tables:
                     model.__table__.create(self.engine, checkfirst=True)
                     sys_log.info(f"[Database] ✅ 建立 AIOps 表: {model.__tablename__}")