feat(trust): ADR-088 Trust Score 持久化 — L4 自動放行核心

TrustScoreManager 從記憶體升級為 PostgreSQL 持久化，
Pod 重啟後信任分數不再歸零，AI 能真正累積到 L4 自動放行門檻。

變更:
- migrations/adr088_trust_score_persistence.sql: trust_records 表
- db/models.py: TrustRecordDB ORM model
- repositories/interfaces.py: ITrustRepository Protocol
- repositories/trust_repository.py: PG upsert ON CONFLICT DO UPDATE
- services/trust_engine.py: bulk_load() 啟動 warm-up
- services/learning_service.py: _persist_trust() + 2 call sites
- main.py: 啟動時 load_all() → bulk_load()

流程: 批准 5 次 → score=5 寫入 DB → Pod 重啟 → warm-up 讀回
      → evaluate_adjusted_risk MEDIUM→LOW → 自動執行

2026-04-17 ogt + Claude Sonnet 4.6（亞太）: ADR-088

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

apps/api/migrations/adr088_trust_score_persistence.sql

@@ -0,0 +1,24 @@
+-- ADR-088: Trust Score 持久化
+-- Phase 4+: TrustScoreManager 從記憶體升級為 PostgreSQL 持久化
+-- 解決問題: Pod 重啟後 AI 信任分數歸零，永遠無法累積到 L4 自動放行門檻
+-- 2026-04-17 ogt + Claude Sonnet 4.6（亞太）
+
+CREATE TABLE IF NOT EXISTS trust_records (
+    action_pattern      VARCHAR(255)    PRIMARY KEY,
+    score               INTEGER         NOT NULL DEFAULT 0,
+    total_approvals     INTEGER         NOT NULL DEFAULT 0,
+    total_rejections    INTEGER         NOT NULL DEFAULT 0,
+    last_approval_by    VARCHAR(100),
+    last_approval_at    TIMESTAMPTZ,
+    last_rejection_by   VARCHAR(100),
+    last_rejection_at   TIMESTAMPTZ,
+    created_at          TIMESTAMPTZ     NOT NULL DEFAULT NOW(),
+    updated_at          TIMESTAMPTZ     NOT NULL DEFAULT NOW()
+);
+
+COMMENT ON TABLE trust_records IS
+    'ADR-088: TrustScoreManager 持久化層。記錄每個 action_pattern 的累積信任分數，'
+    '跨 Pod 重啟存活。score >= 5 → MEDIUM 自動降 LOW，score >= 10 → HIGH 降 MEDIUM。';
+
+CREATE INDEX IF NOT EXISTS ix_trust_records_score ON trust_records (score DESC);
+CREATE INDEX IF NOT EXISTS ix_trust_records_updated ON trust_records (updated_at DESC);

apps/api/src/db/models.py

@@ -1175,3 +1175,56 @@ class AiGovernanceEvent(Base):
         Index("ix_ai_governance_triggered_at", "triggered_at"),
         Index("ix_ai_governance_resolved", "resolved"),
     )
+
+
+# =============================================================================
+# TrustRecordDB - ADR-088 TrustScore 持久化
+# =============================================================================
+
+class TrustRecordDB(Base):
+    """
+    Trust Score 持久化記錄
+
+    ADR-088: TrustScoreManager 從記憶體升級為 PostgreSQL 持久化。
+    Pod 重啟後分數不歸零，AI 能真正累積信任達到 L4 自動放行。
+
+    score >= 5:  MEDIUM → LOW (自動執行)
+    score >= 10: HIGH → MEDIUM (降一級)
+
+    2026-04-17 ogt + Claude Sonnet 4.6（亞太）: Phase 4 信任持久化
+    """
+    __tablename__ = "trust_records"
+
+    action_pattern: Mapped[str] = mapped_column(
+        String(255), primary_key=True,
+        comment="操作模式，例如 delete:nginx-frontend-*"
+    )
+    score: Mapped[int] = mapped_column(
+        Integer, nullable=False, default=0,
+        comment="累積信任分數。+1/approve，reject 歸零"
+    )
+    total_approvals: Mapped[int] = mapped_column(
+        Integer, nullable=False, default=0,
+    )
+    total_rejections: Mapped[int] = mapped_column(
+        Integer, nullable=False, default=0,
+    )
+    last_approval_by: Mapped[str | None] = mapped_column(String(100), nullable=True)
+    last_approval_at: Mapped[datetime | None] = mapped_column(
+        DateTime(timezone=True), nullable=True,
+    )
+    last_rejection_by: Mapped[str | None] = mapped_column(String(100), nullable=True)
+    last_rejection_at: Mapped[datetime | None] = mapped_column(
+        DateTime(timezone=True), nullable=True,
+    )
+    created_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), nullable=False, default=taipei_now,
+    )
+    updated_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), nullable=False, default=taipei_now, onupdate=taipei_now,
+    )
+
+    __table_args__ = (
+        Index("ix_trust_records_score", "score"),
+        Index("ix_trust_records_updated", "updated_at"),
+    )

apps/api/src/main.py

@@ -302,6 +302,19 @@ async def lifespan(_app: FastAPI) -> AsyncGenerator[None, None]:
     except Exception as e:
         logger.warning("working_memory_warmup_failed", error=str(e))
 
+    # ADR-088: Trust Score 冷啟動 — 從 PostgreSQL 恢復信任分數
+    # 解決: Pod 重啟後 TrustScoreManager 記憶歸零，AI 永遠無法累積到 L4 自動放行
+    # 2026-04-17 ogt + Claude Sonnet 4.6（亞太）: Phase 4 信任持久化
+    try:
+        from src.repositories.trust_repository import get_trust_repository
+        from src.services.trust_engine import get_trust_manager
+
+        trust_records = await get_trust_repository().load_all()
+        loaded = get_trust_manager().bulk_load(trust_records)
+        logger.info("trust_scores_warmed_up", loaded=loaded)
+    except Exception as e:
+        logger.warning("trust_scores_warmup_failed", error=str(e))
+
     # Phase 4 飛輪修復: Playbook Embedding 冷啟動索引
     # 2026-04-10 Claude Sonnet 4.6 Asia/Taipei
     # 目的: 確保 playbook_embeddings 表有最新向量，供語義相似度查詢

apps/api/src/repositories/interfaces.py

@@ -13,6 +13,7 @@ Phase 16 R3: Repository 層 Protocol 介面
 建立者: Claude Code (Phase 16 架構重構)
 """
 
+from datetime import datetime
 from typing import Protocol, runtime_checkable
 from uuid import UUID
 
@@ -639,3 +640,40 @@ class IFailureWatcher(Protocol):
             (success, result_message)
         """
         ...
+
+
+@runtime_checkable
+class ITrustRepository(Protocol):
+    """
+    Trust Repository Protocol
+
+    職責: TrustRecord 持久化 (PostgreSQL)
+    實作: TrustRepository
+
+    ADR-088: TrustScoreManager 持久化層
+    2026-04-17 ogt + Claude Sonnet 4.6（亞太）: Phase 4 信任持久化
+    """
+
+    async def upsert(
+        self,
+        action_pattern: str,
+        score: int,
+        total_approvals: int,
+        total_rejections: int,
+        last_approval_by: str | None = None,
+        last_approval_at: datetime | None = None,
+        last_rejection_by: str | None = None,
+        last_rejection_at: datetime | None = None,
+    ) -> bool:
+        """INSERT or UPDATE trust record (upsert by action_pattern)"""
+        ...
+
+    async def load_all(self) -> list[dict]:
+        """
+        載入所有 trust records 供啟動 warm-up
+
+        Returns:
+            list[{action_pattern, score, total_approvals, total_rejections,
+                  last_approval_by, last_approval_at, last_rejection_by, last_rejection_at}]
+        """
+        ...

apps/api/src/repositories/trust_repository.py

@@ -0,0 +1,145 @@
+"""
+Trust Repository - PostgreSQL 持久化層
+======================================
+ADR-088: TrustScoreManager 持久化升級
+
+職責: trust_records 表的 upsert / load_all
+設計: 實作 ITrustRepository Protocol
+
+Pod 重啟後信任分數不歸零，AI 能真正累積到 L4 自動放行門檻。
+
+2026-04-17 ogt + Claude Sonnet 4.6（亞太）: Phase 4 信任持久化
+"""
+
+from datetime import datetime
+
+import structlog
+from sqlalchemy import select
+from sqlalchemy.dialects.postgresql import insert as pg_insert
+
+from src.db.base import get_db_context
+from src.db.models import TrustRecordDB
+from src.repositories.interfaces import ITrustRepository
+
+logger = structlog.get_logger(__name__)
+
+
+class TrustRepository:
+    """
+    Trust Repository 實作（PostgreSQL）
+
+    使用 PostgreSQL ON CONFLICT DO UPDATE (upsert)，
+    保證並行安全且無競爭條件。
+    """
+
+    async def upsert(
+        self,
+        action_pattern: str,
+        score: int,
+        total_approvals: int,
+        total_rejections: int,
+        last_approval_by: str | None = None,
+        last_approval_at: datetime | None = None,
+        last_rejection_by: str | None = None,
+        last_rejection_at: datetime | None = None,
+    ) -> bool:
+        """
+        INSERT or UPDATE trust record。
+
+        使用 PostgreSQL upsert 保證並行安全。
+        action_pattern 是主鍵，衝突時更新除 created_at 外的所有欄位。
+        """
+        from src.utils.timezone import now_taipei
+
+        try:
+            async with get_db_context() as db:
+                stmt = pg_insert(TrustRecordDB).values(
+                    action_pattern=action_pattern,
+                    score=score,
+                    total_approvals=total_approvals,
+                    total_rejections=total_rejections,
+                    last_approval_by=last_approval_by,
+                    last_approval_at=last_approval_at,
+                    last_rejection_by=last_rejection_by,
+                    last_rejection_at=last_rejection_at,
+                    created_at=now_taipei(),
+                    updated_at=now_taipei(),
+                ).on_conflict_do_update(
+                    index_elements=["action_pattern"],
+                    set_={
+                        "score": score,
+                        "total_approvals": total_approvals,
+                        "total_rejections": total_rejections,
+                        "last_approval_by": last_approval_by,
+                        "last_approval_at": last_approval_at,
+                        "last_rejection_by": last_rejection_by,
+                        "last_rejection_at": last_rejection_at,
+                        "updated_at": now_taipei(),
+                    },
+                )
+                await db.execute(stmt)
+
+            logger.debug(
+                "trust_record_upserted",
+                action_pattern=action_pattern,
+                score=score,
+            )
+            return True
+
+        except Exception as e:
+            logger.error(
+                "trust_record_upsert_failed",
+                action_pattern=action_pattern,
+                error=str(e),
+            )
+            return False
+
+    async def load_all(self) -> list[dict]:
+        """
+        載入所有 trust records，供啟動 warm-up。
+
+        Returns:
+            list[dict] — 每筆含 action_pattern, score, total_approvals,
+            total_rejections, last_approval_by, last_approval_at,
+            last_rejection_by, last_rejection_at
+        """
+        try:
+            async with get_db_context() as db:
+                result = await db.execute(select(TrustRecordDB))
+                rows = result.scalars().all()
+
+            records = [
+                {
+                    "action_pattern": r.action_pattern,
+                    "score": r.score,
+                    "total_approvals": r.total_approvals,
+                    "total_rejections": r.total_rejections,
+                    "last_approval_by": r.last_approval_by,
+                    "last_approval_at": r.last_approval_at,
+                    "last_rejection_by": r.last_rejection_by,
+                    "last_rejection_at": r.last_rejection_at,
+                }
+                for r in rows
+            ]
+
+            logger.info("trust_records_loaded", count=len(records))
+            return records
+
+        except Exception as e:
+            logger.error("trust_records_load_failed", error=str(e))
+            return []
+
+
+# =============================================================================
+# Singleton
+# =============================================================================
+
+_repository: TrustRepository | None = None
+
+
+def get_trust_repository() -> ITrustRepository:
+    """取得 TrustRepository 單例"""
+    global _repository
+    if _repository is None:
+        _repository = TrustRepository()
+    return _repository

apps/api/src/services/learning_service.py

@@ -32,8 +32,9 @@ import structlog
 
 from src.models.approval import ApprovalRequest
 from src.models.incident import IncidentStatus
-from src.repositories.interfaces import ILearningRepository
+from src.repositories.interfaces import ILearningRepository, ITrustRepository
 from src.repositories.learning_repository import get_learning_repository
+from src.repositories.trust_repository import get_trust_repository
 from src.services.trust_engine import get_trust_manager
 
 logger = structlog.get_logger(__name__)
@@ -156,9 +157,11 @@ class LearningService:
     def __init__(
         self,
         repository: ILearningRepository | None = None,
+        trust_repository: ITrustRepository | None = None,
     ):
         self._trust_manager = get_trust_manager()
         self._repository = repository or get_learning_repository()
+        self._trust_repo = trust_repository or get_trust_repository()
 
     async def process_execution_result(
         self,
@@ -200,6 +203,9 @@ class LearningService:
             )
             feedback_type = FeedbackType.EXECUTION_FAILURE
 
+        # ADR-088: 持久化信任分數到 PostgreSQL (Pod 重啟後不歸零)
+        await self._persist_trust(action_pattern)
+
         # 取得更新後的信任分數
         trust_record = self._trust_manager.get_trust_record(action_pattern)
         trust_after = trust_record.score if trust_record else 0
@@ -325,6 +331,9 @@ class LearningService:
                     )
                     playbook_updated = await self._demote_playbook(feedback.incident_id)
 
+        # ADR-088: 持久化信任分數到 PostgreSQL (Pod 重啟後不歸零)
+        await self._persist_trust(action_pattern)
+
         trust_record = self._trust_manager.get_trust_record(action_pattern)
         trust_after = trust_record.score if trust_record else 0
 
@@ -955,6 +964,36 @@ class LearningService:
             "learning_status": learning_status,
         }
 
+    async def _persist_trust(self, action_pattern: str) -> None:
+        """
+        将内存中的 TrustRecord 持久化到 PostgreSQL。
+
+        ADR-088: 每次 approve/reject 後同步寫入 DB，
+        確保 Pod 重啟後信任分數不歸零。
+
+        2026-04-17 ogt + Claude Sonnet 4.6（亞太）: Phase 4 信任持久化
+        """
+        record = self._trust_manager.get_trust_record(action_pattern)
+        if not record:
+            return
+        try:
+            await self._trust_repo.upsert(
+                action_pattern=action_pattern,
+                score=record.score,
+                total_approvals=record.total_approvals,
+                total_rejections=record.total_rejections,
+                last_approval_by=record.last_approval_by,
+                last_approval_at=record.last_approval_at,
+                last_rejection_by=record.last_rejection_by,
+                last_rejection_at=record.last_rejection_at,
+            )
+        except Exception as e:
+            logger.warning(
+                "trust_persist_failed",
+                action_pattern=action_pattern,
+                error=str(e),
+            )
+
     def _get_action_tier(self, action: str) -> int:
         """取得動作的 Tier"""
         tier_actions = {

apps/api/src/services/trust_engine.py

@@ -362,6 +362,46 @@ class TrustScoreManager:
             record.score = 0
         logger.warning("[TrustEngine] All trust scores reset!")
 
+    def bulk_load(self, records: list[dict]) -> int:
+        """
+        從 DB 批量載入 trust records 到記憶體（啟動 warm-up 用）。
+
+        ADR-088: Pod 重啟後從 PostgreSQL 恢復信任分數，
+        確保 AI 不會因重啟而失憶歸零。
+
+        Args:
+            records: list[dict] — 每筆含 action_pattern, score,
+                     total_approvals, total_rejections,
+                     last_approval_by, last_approval_at,
+                     last_rejection_by, last_rejection_at
+
+        Returns:
+            int: 載入筆數
+
+        2026-04-17 ogt + Claude Sonnet 4.6（亞太）: ADR-088
+        """
+        loaded = 0
+        for r in records:
+            pattern = r.get("action_pattern")
+            if not pattern:
+                continue
+            record = TrustRecord(
+                action_pattern=pattern,
+                score=r.get("score", 0),
+                total_approvals=r.get("total_approvals", 0),
+                total_rejections=r.get("total_rejections", 0),
+                last_approval_by=r.get("last_approval_by"),
+                last_approval_at=r.get("last_approval_at"),
+                last_rejection_by=r.get("last_rejection_by"),
+                last_rejection_at=r.get("last_rejection_at"),
+            )
+            self._records[pattern] = record
+            loaded += 1
+
+        if loaded:
+            logger.info(f"[TrustEngine] Warm-up: loaded {loaded} trust records from DB")
+        return loaded
+
 
 # ==================== Pattern Matching Utilities ====================