feat(aiops): add mcp agent loop foundation

apps/api/src/db/models.py

@@ -19,6 +19,7 @@ from sqlalchemy import (
     BigInteger,
     Boolean,
     CheckConstraint,
+    Date,
     DateTime,
     Float,
     Index,
@@ -456,6 +457,90 @@ class AuditLog(Base):
     )
 
 
+# =============================================================================
+# MCP Audit / Snapshots — 2026-05-01 ghost-loop + MCP governance
+# =============================================================================
+
+class MCPAuditLog(Base):
+    """Durable audit trail for every MCP tool call."""
+
+    __tablename__ = "mcp_audit_log"
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    session_id: Mapped[str] = mapped_column(String(36), nullable=False)
+    flywheel_node: Mapped[str | None] = mapped_column(String(20), nullable=True)
+    mcp_server: Mapped[str] = mapped_column(String(80), nullable=False)
+    tool_name: Mapped[str] = mapped_column(String(120), nullable=False)
+    input_params: Mapped[dict | None] = mapped_column(JSONB, nullable=True)
+    output_result: Mapped[dict | list | str | None] = mapped_column(JSONB, nullable=True)
+    duration_ms: Mapped[int | None] = mapped_column(Integer, nullable=True)
+    success: Mapped[bool | None] = mapped_column(Boolean, nullable=True)
+    error_message: Mapped[str | None] = mapped_column(Text, nullable=True)
+    incident_id: Mapped[str | None] = mapped_column(String(64), nullable=True)
+    agent_role: Mapped[str | None] = mapped_column(String(40), nullable=True)
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=taipei_now)
+
+    __table_args__ = (
+        Index("idx_mcp_audit_session", "session_id"),
+        Index("idx_mcp_audit_incident", "incident_id"),
+        Index("idx_mcp_audit_node", "flywheel_node", "created_at"),
+        Index("idx_mcp_audit_server_tool", "mcp_server", "tool_name", "created_at"),
+        Index("idx_mcp_audit_agent_role", "agent_role", "created_at"),
+    )
+
+
+class MCPDailyStats(Base):
+    """Daily aggregate for MCP provider/tool success rate and latency."""
+
+    __tablename__ = "mcp_daily_stats"
+
+    date: Mapped[datetime] = mapped_column(Date, primary_key=True)
+    mcp_server: Mapped[str] = mapped_column(String(80), primary_key=True)
+    tool_name: Mapped[str] = mapped_column(String(120), primary_key=True)
+    call_count: Mapped[int] = mapped_column(Integer, default=0, nullable=False)
+    success_count: Mapped[int] = mapped_column(Integer, default=0, nullable=False)
+    avg_duration_ms: Mapped[float | None] = mapped_column(Float, nullable=True)
+
+
+class K8sStateSnapshot(Base):
+    """Pre/post Kubernetes resource state snapshots for remediation verification."""
+
+    __tablename__ = "k8s_state_snapshots"
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    incident_id: Mapped[str | None] = mapped_column(String(64), nullable=True)
+    snapshot_type: Mapped[str] = mapped_column(String(40), nullable=False)
+    namespace: Mapped[str | None] = mapped_column(String(63), nullable=True)
+    resource_type: Mapped[str | None] = mapped_column(String(80), nullable=True)
+    resource_name: Mapped[str | None] = mapped_column(String(253), nullable=True)
+    state_json: Mapped[dict | None] = mapped_column(JSONB, nullable=True)
+    captured_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=taipei_now)
+
+    __table_args__ = (
+        Index("idx_k8s_snapshot_incident", "incident_id"),
+        Index("idx_k8s_snapshot_resource", "namespace", "resource_type", "resource_name"),
+        Index("idx_k8s_snapshot_captured", "captured_at"),
+    )
+
+
+class PrometheusSnapshot(Base):
+    """Prometheus query snapshots for detect/verify flywheel stages."""
+
+    __tablename__ = "prometheus_snapshots"
+
+    id: Mapped[int] = mapped_column(BigInteger, primary_key=True, autoincrement=True)
+    incident_id: Mapped[str | None] = mapped_column(String(64), nullable=True)
+    query: Mapped[str] = mapped_column(Text, nullable=False)
+    result_json: Mapped[dict | list | str | None] = mapped_column(JSONB, nullable=True)
+    snapshot_type: Mapped[str | None] = mapped_column(String(40), nullable=True)
+    captured_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), default=taipei_now)
+
+    __table_args__ = (
+        Index("idx_prom_snapshot_incident", "incident_id"),
+        Index("idx_prom_snapshot_type", "snapshot_type", "captured_at"),
+    )
+
+
 # =============================================================================
 # 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」