feat(agent): upgrade langchain to v1.0+

app/schemas/agent.py

@@ -1,38 +1,37 @@
 """AI智能体相关数据模型"""
 
 from datetime import datetime
-from typing import Dict, List, Optional, Any
+from typing import List, Optional
+
+from langchain_core.messages import BaseMessage
 from pydantic import BaseModel, Field, ConfigDict, field_serializer
 
 
 class ConversationMemory(BaseModel):
     """对话记忆模型"""
-    
+
     session_id: str = Field(description="会话ID")
     user_id: Optional[str] = Field(default=None, description="用户ID")
-    title: Optional[str] = Field(default=None, description="会话标题")
-    messages: List[Dict[str, Any]] = Field(default_factory=list, description="消息列表")
-    context: Dict[str, Any] = Field(default_factory=dict, description="会话上下文")
-    created_at: datetime = Field(default_factory=datetime.now, description="创建时间")
+    messages: List[BaseMessage] = Field(default_factory=list, description="消息列表")
     updated_at: datetime = Field(default_factory=datetime.now, description="更新时间")
-    
+
     model_config = ConfigDict()
-    
-    @field_serializer('created_at', 'updated_at', when_used='json')
+
+    @field_serializer('updated_at', when_used='json')
     def serialize_datetime(self, value: datetime) -> str:
         return value.isoformat()
 
 
 class AgentState(BaseModel):
     """AI智能体状态模型"""
-    
+
     session_id: str = Field(description="会话ID")
     current_task: Optional[str] = Field(default=None, description="当前任务")
     is_thinking: bool = Field(default=False, description="是否正在思考")
     last_activity: datetime = Field(default_factory=datetime.now, description="最后活动时间")
-    
+
     model_config = ConfigDict()
-    
+
     @field_serializer('last_activity', when_used='json')
     def serialize_datetime(self, value: datetime) -> str:
         return value.isoformat()
@@ -40,7 +39,7 @@ class AgentState(BaseModel):
 
 class UserMessage(BaseModel):
     """用户消息模型"""
-    
+
     session_id: str = Field(description="会话ID")
     content: str = Field(description="消息内容")
     user_id: Optional[str] = Field(default=None, description="用户ID")
@@ -50,7 +49,7 @@ class UserMessage(BaseModel):
 
 class ToolResult(BaseModel):
     """工具执行结果模型"""
-    
+
     session_id: str = Field(description="会话ID")
     call_id: str = Field(description="调用ID")
     success: bool = Field(description="是否成功")