fix(rls): 收斂 API DB access context

apps/api/src/services/ai_router.py

@@ -842,14 +842,13 @@ class AIRouter:
             空 dict 代表無資料或查詢失敗（caller 應降級為忽略）。
         """
         try:
-            from src.db.base import get_session_factory
+            from src.db.base import get_db_context
             from src.repositories.aider_event_repository import AiderEventRepository
         except ImportError:
             return {}
 
         try:
-            sf = get_session_factory()
-            async with sf() as sess:
+            async with get_db_context() as sess:
                 repo_obj = AiderEventRepository(sess)
                 stats = await repo_obj.model_stats_since(days=days)
         except Exception:

apps/api/src/services/ai_slo_calculator.py

@@ -28,7 +28,7 @@ from datetime import timedelta
 import structlog
 from sqlalchemy import func, select, text
 
-from src.db.base import get_session_factory
+from src.db.base import get_db_context
 from src.db.models import AiGovernanceEvent, AutoRepairExecution, ApprovalRecord
 from src.utils.timezone import now_taipei
 
@@ -127,7 +127,7 @@ class AiSloCalculator:
         try:
             since = now_taipei() - timedelta(days=SLO_WINDOW_DAYS)
 
-            async with get_session_factory()() as session:
+            async with get_db_context() as session:
                 slo1 = await self._calc_auto_success_rate(session, since)
                 slo2 = await self._calc_human_override_rate(session, since)
                 slo3 = await self._calc_false_neg_rate(session, since)
@@ -210,7 +210,7 @@ class AiSloCalculator:
         只在 any_violated=True 時呼叫。不管舊違反是否解決。
         """
         try:
-            async with get_session_factory()() as session:
+            async with get_db_context() as session:
                 event = AiGovernanceEvent(
                     event_type="slo_violation",
                     details=report.to_dict(),

apps/api/src/services/decision_manager.py

@@ -1933,14 +1933,14 @@ class DecisionManager:
         try:
             from src.core.feature_flags import aiops_flags as _p6_flags
             if _p6_flags.is_sub_flag_enabled("AIOPS_P6_SELF_DEMOTION"):
-                from src.db.base import get_session_factory as _p6_sf
+                from src.db.base import get_db_context as _p6_db_context
                 from src.db.models import AiGovernanceEvent as _GovernanceEvent
                 from sqlalchemy import select as _p6_select, func as _p6_func
                 from datetime import timedelta as _p6_td
 
                 _now = __import__("src.utils.timezone", fromlist=["now_taipei"]).now_taipei()
 
-                async with _p6_sf()() as _p6_sess:
+                async with _p6_db_context() as _p6_sess:
                     # 過去 7 天有幾筆未解決的 slo_violation？
                     _viol_7d_q = await _p6_sess.execute(
                         _p6_select(_p6_func.count()).where(
@@ -1980,8 +1980,8 @@ class DecisionManager:
                     )
                     # 記錄保守模式事件
                     try:
-                        from src.db.base import get_session_factory as _p6_sf2
-                        async with _p6_sf2()() as _s2:
+                        from src.db.base import get_db_context as _p6_db_context2
+                        async with _p6_db_context2() as _s2:
                             _s2.add(_GovernanceEvent(
                                 event_type="conservative_mode",
                                 details={
@@ -2021,8 +2021,8 @@ class DecisionManager:
                             _push_decision_to_telegram(incident, token.proposal_data)
                         )
                         try:
-                            from src.db.base import get_session_factory as _p6_sf3
-                            async with _p6_sf3()() as _s3:
+                            from src.db.base import get_db_context as _p6_db_context3
+                            async with _p6_db_context3() as _s3:
                                 _s3.add(_GovernanceEvent(
                                     event_type="self_demotion",
                                     details={

apps/api/src/services/dynamic_baseline_service.py

@@ -424,11 +424,10 @@ class DynamicBaselineService:
     async def _pg_upsert_baseline(self, state: BaselineState, promql: str, lookback_hours: int) -> None:
         """寫入 DynamicBaselineRecord 到 PostgreSQL（INSERT，不更新舊記錄）"""
         try:
-            from src.db.base import get_session_factory
+            from src.db.base import get_db_context
             from src.db.models import DynamicBaselineRecord
 
-            factory = get_session_factory()
-            async with factory() as session:
+            async with get_db_context() as session:
                 record = DynamicBaselineRecord(
                     metric_name=state.metric_name,
                     mean=state.mean,
@@ -449,11 +448,10 @@ class DynamicBaselineService:
         try:
             from sqlalchemy import select
 
-            from src.db.base import get_session_factory
+            from src.db.base import get_db_context
             from src.db.models import DynamicBaselineRecord
 
-            factory = get_session_factory()
-            async with factory() as session:
+            async with get_db_context() as session:
                 stmt = (
                     select(DynamicBaselineRecord)
                     .where(DynamicBaselineRecord.metric_name == metric_name)

apps/api/src/services/finetune_exporter.py

@@ -52,7 +52,7 @@ from pathlib import Path
 import structlog
 from sqlalchemy import and_, select, text as sql_text
 
-from src.db.base import get_session_factory
+from src.db.base import get_db_context
 from src.db.models import AgentSession, AutoRepairExecution, IncidentEvidence
 from src.utils.timezone import now_taipei
 
@@ -107,9 +107,7 @@ class FineTuneExporter:
 
     async def _run_export(self) -> tuple[str | None, int]:
         cutoff = now_taipei() - timedelta(days=EXPORT_LOOKBACK_DAYS)
-        session_factory = get_session_factory()
-
-        async with session_factory() as db:
+        async with get_db_context() as db:
             # 1. 取得成功驗證的 EvidenceSnapshot（有 evidence_summary + verification_result='success'）
             stmt = select(IncidentEvidence).where(
                 and_(
@@ -153,7 +151,7 @@ class FineTuneExporter:
                 with open(output_path, 'rb') as _f:
                     _checksum = hashlib.sha256(_f.read()).hexdigest()
             _ids = [str(ev.id) for ev in evidences]
-            async with session_factory() as _db:
+            async with get_db_context() as _db:
                 await _db.execute(
                     sql_text("""
                         INSERT INTO finetune_exports (

apps/api/src/services/log_anomaly_detector.py

@@ -296,12 +296,11 @@ class LogAnomalyDetector:
         """
         try:
             from sqlalchemy.dialects.postgresql import insert as pg_insert
-            from src.db.base import get_session_factory
+            from src.db.base import get_db_context
             from src.db.models import LogClusterRecord
             from src.utils.timezone import now_taipei
 
-            factory = get_session_factory()
-            async with factory() as session:
+            async with get_db_context() as session:
                 stmt = pg_insert(LogClusterRecord).values(
                     cluster_id=cluster.cluster_id,
                     template=cluster.template,

apps/api/src/services/trust_drift_detector.py

@@ -39,7 +39,7 @@ from dataclasses import dataclass
 import structlog
 from sqlalchemy import func, select
 
-from src.db.base import get_session_factory
+from src.db.base import get_db_context
 from src.db.models import AiGovernanceEvent, PlaybookRecord
 from src.utils.timezone import now_taipei
 
@@ -115,7 +115,7 @@ class TrustDriftDetector:
             TrustDistribution（樣本不足時 drift_detected=False）
         """
         try:
-            async with get_session_factory()() as session:
+            async with get_db_context() as session:
                 # 只計算 approved 狀態的 Playbook
                 total_q = await session.execute(
                     select(func.count()).where(
@@ -215,7 +215,7 @@ class TrustDriftDetector:
     async def save_drift_event(self, dist: TrustDistribution) -> None:
         """將信任度漂移事件寫入 ai_governance_events。"""
         try:
-            async with get_session_factory()() as session:
+            async with get_db_context() as session:
                 event = AiGovernanceEvent(
                     event_type="trust_drift",
                     details={