```

feat(ai_agent): 完善AI适配器和服务功能

- 添加OpenClaw和Hermes健康检查接口
- 实现OpenClaw工具调用功能
- 重构AI适配器使用常量定义
- 增加AI技能系统支持
- 更新配置文件中的默认模型提供者设置

refactor(scheduler): 使用常量替换硬编码值

- 将硬编码的actor值替换为ActorValue常量
- 将receive_id_type替换为FeishuReceiveIdType枚举

refactor(audit): 统一审计日志常量使用

- 将硬编码的actor、source、risk_level等值替换为对应常量
- 更新审核服务中的状态和操作常量引用

refactor(approvals): 标准化审批模块常量使用

- 将applicant默认值替换为ActorValue.API常量
- 使用ApprovalStatus常量替代硬编码状态值
- 更新审核操作常量引用
```

app/modules/audit/constants.py

@@ -0,0 +1,39 @@
+from enum import StrEnum
+
+
+class AuditAction(StrEnum):
+    AI_ASK = "ai.ask"
+    AI_PROVIDER_HEALTH = "ai.provider_health"
+    OPENCLAW_TOOLS_INVOKE = "openclaw.tools.invoke"
+    GENERATE_EVENTS = "generate_events"
+    FEISHU_SEND_TEXT = "send_text"
+    FEISHU_SEND_CARD = "send_card"
+    APPROVAL_CREATE = "approval.create"
+    APPROVAL_APPROVE = "approval.approve"
+    APPROVAL_REJECT = "approval.reject"
+    LEGACY_SYNC_PROJECTS = "sync_projects"
+
+
+class AuditRiskLevel(StrEnum):
+    LOW = "low"
+    MEDIUM = "medium"
+    HIGH = "high"
+
+
+class AuditSource(StrEnum):
+    API = "api"
+    OPENCLAW = "openclaw"
+    RISK = "risk"
+    FEISHU = "feishu"
+    APPROVAL = "approval"
+    LEGACY_MYSQL = "legacy_mysql"
+
+
+class AuditTargetType(StrEnum):
+    AI = "ai"
+    OPENCLAW_TOOL = "openclaw_tool"
+    RISK_EVENTS = "risk-events"
+
+
+class AuditStatus(StrEnum):
+    SUCCESS = "success"