feat(auto-repair): 所有操作強制寫入 DB — auto_repair_executions 表

統帥指令: 所有自動修復操作（成功/失敗）必須持久化

變更:
- migrations/phase10_auto_repair_executions.sql: 新增表 + 4 個索引
- db/models.py: 新增 AutoRepairExecution SQLAlchemy model
- repositories/audit_log_repository.py: 新增 AutoRepairExecutionRepository (create/list_by_incident/get_stats)
- auto_repair_service.py: execute_auto_repair 成功/失敗分支都寫入 DB
  - 新增 similarity_score 參數傳遞
  - AutoRepairDecision 新增 similarity_score 欄位
- webhooks.py: 傳入 similarity_score 到 execute_auto_repair

已執行 migration: awoooi_prod@192.168.0.188:5432 ✅

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/api/src/db/models.py

@@ -352,6 +352,50 @@ class AuditLog(Base):
     )
 
 
+# =============================================================================
+# AutoRepairExecution - Phase 10 操作記錄
+# 2026-04-08 Claude Code: 統帥指令「所有操作都必須被記錄，寫入資料庫」
+# =============================================================================
+
+class AutoRepairExecution(Base):
+    """
+    自動修復執行記錄
+
+    每次 evaluate_auto_repair 觸發並執行 (成功或失敗) 都寫入此表。
+    不依賴 approval_id（自動修復不需人工批准）。
+    """
+    __tablename__ = "auto_repair_executions"
+
+    id: Mapped[str] = mapped_column(String(36), primary_key=True, default=generate_uuid)
+
+    # 關聯
+    incident_id: Mapped[str] = mapped_column(String(30), nullable=False, index=True)
+    playbook_id: Mapped[str] = mapped_column(String(36), nullable=False, index=True)
+    playbook_name: Mapped[str] = mapped_column(String(200), nullable=False)
+
+    # 執行結果
+    success: Mapped[bool] = mapped_column(default=False, nullable=False)
+    executed_steps: Mapped[list] = mapped_column(JSON, default=list, nullable=False)
+    error_message: Mapped[str | None] = mapped_column(Text, nullable=True)
+
+    # 執行上下文
+    triggered_by: Mapped[str] = mapped_column(
+        String(50), default="auto_repair", nullable=False,
+        comment="auto_repair / cold_start_trust",
+    )
+    similarity_score: Mapped[float | None] = mapped_column(nullable=True)
+    risk_level: Mapped[str | None] = mapped_column(String(20), nullable=True)
+    execution_time_ms: Mapped[int | None] = mapped_column(Integer, nullable=True)
+
+    # 時間戳 (台北時區)
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=taipei_now)
+
+    __table_args__ = (
+        Index("ix_are_created_at", "created_at"),
+        Index("ix_are_success", "success"),
+    )
+
+
 # =============================================================================
 # IncidentRecord - Phase 6.2 Episodic Memory (PostgreSQL)
 # =============================================================================