```

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/ai_agent/constants.py

@@ -0,0 +1,128 @@
+from enum import StrEnum
+
+
+class AIProviderName(StrEnum):
+    NOOP = "noop"
+    OPENCLAW = "openclaw"
+    HERMES = "hermes"
+    OPENCLAW_HERMES = "openclaw_hermes"
+    OPENCLAW_HERMES_DASH = "openclaw-hermes"
+    HYBRID = "hybrid"
+    DIRECT_LLM = "direct_llm"
+
+
+class AIResponseKey(StrEnum):
+    PROVIDER = "provider"
+    ANSWER = "answer"
+    RAW = "raw"
+    RESULT = "result"
+    OK = "ok"
+    ERROR = "error"
+    MESSAGE = "message"
+    TYPE = "type"
+    BASE_URL = "base_url"
+    HEALTH = "health"
+    HEALTHZ = "healthz"
+    READYZ = "readyz"
+    DATA = "data"
+    STATUS_CODE = "status_code"
+    TEXT = "text"
+    PIPELINE = "pipeline"
+    HERMES_RECALL = "hermes_recall"
+    HERMES_ANSWER = "hermes_answer"
+    HERMES_REMEMBER = "hermes_remember"
+    OPENCLAW = "openclaw"
+    TOOL = "tool"
+    TOOL_INVOKED = "tool_invoked"
+    TOOL_ERROR = "tool_error"
+
+
+class AIRequestKey(StrEnum):
+    PROMPT = "prompt"
+    CONTEXT = "context"
+
+
+class AIContextKey(StrEnum):
+    OPENCLAW_TOOL = "openclaw_tool"
+    OPENCLAW_ACTION = "openclaw_action"
+    OPENCLAW_ARGS = "openclaw_args"
+    OPENCLAW_SESSION_KEY = "openclaw_session_key"
+    AGENT_PIPELINE = "agent_pipeline"
+    HERMES_MEMORY = "hermes_memory"
+    OPENCLAW = "openclaw"
+    MODE = "mode"
+    USER_PROMPT = "user_prompt"
+    REQUEST_CONTEXT = "request_context"
+    ASSISTANT_ANSWER = "assistant_answer"
+
+
+class AIMemoryMode(StrEnum):
+    RECALL = "memory_recall"
+    WRITE = "memory_write"
+
+
+class AIHttpPath(StrEnum):
+    CHAT_COMPLETIONS = "/chat/completions"
+    HEALTH = "/health"
+    HEALTHZ = "/healthz"
+    READYZ = "/readyz"
+    TOOLS_INVOKE = "/tools/invoke"
+    V1 = "/v1"
+
+
+class AIHttpHeader(StrEnum):
+    AUTHORIZATION = "Authorization"
+    HERMES_SESSION_ID = "X-Hermes-Session-Id"
+
+
+class AIHttpPayloadKey(StrEnum):
+    MODEL = "model"
+    MESSAGES = "messages"
+    ROLE = "role"
+    CONTENT = "content"
+    STREAM = "stream"
+    TOOL = "tool"
+    ACTION = "action"
+    ARGS = "args"
+    SESSION_KEY = "sessionKey"
+    CHOICES = "choices"
+    MESSAGE = "message"
+
+
+class AIChatRole(StrEnum):
+    SYSTEM = "system"
+    USER = "user"
+
+
+class AIDefault(StrEnum):
+    ACTION_JSON = "json"
+    SESSION_KEY_MAIN = "main"
+
+
+class AIRiskPreference(StrEnum):
+    BALANCED = "balanced"
+
+
+class AIErrorKey(StrEnum):
+    OPENCLAW = "openclaw_error"
+    HERMES = "hermes_error"
+    DIRECT_LLM = "llm_error"
+
+
+OPENCLAW_HERMES_PIPELINE = (
+    "hermes_recall -> openclaw_gateway -> hermes_answer -> hermes_remember"
+)
+COMPANY_MANAGEMENT_SYSTEM_INSTRUCTIONS = (
+    "You are a company management AI. Be concise, cite data from context, "
+    "and never approve payments, performance changes, or trades automatically."
+)
+CHAT_USER_CONTENT_TEMPLATE = "Context:\n{context}\n\nTask:\n{task}"
+AUTHORIZATION_BEARER_TEMPLATE = "Bearer {token}"
+NOOP_PROVIDER_ANSWER = (
+    "AI provider is not configured yet. This is a deterministic placeholder. "
+    "Set MODEL_PROVIDER to openclaw_hermes, openclaw, hermes, or direct_llm "
+    "after credentials are ready."
+)
+OPENCLAW_TOOL_COMPLETED_ANSWER = "OpenClaw tool invocation completed."
+DIRECT_LLM_API_KEY_MISSING = "DIRECT_LLM_API_KEY is not configured"
+UNEXPECTED_HERMES_RESPONSE = "Unexpected chat completion response"