feat: UI重构 - 历史对话列表页 + 新建按钮顶部右侧 + 删除功能

用户指出SiliconFlow平台确实支持标准tool消息类型，之前的修改是错误的

版本: v3.0.7

main_v2.py

@@ -647,17 +647,19 @@ async def get_conversations(db: Session = Depends(get_db)):
     user = conv_service.get_or_create_user(MAIN_USER_ID, display_name="主用户", user_type='web')
     conversations = conv_service.get_user_conversations(user.id)
     
-    return {
-        "conversations": [
-            {
-                "id": c.conversation_id,
-                "title": c.title or "新对话",
-                "created_at": c.created_at.isoformat(),
-                "updated_at": c.updated_at.isoformat()
-            }
-            for c in conversations
-        ]
-    }
+    # 为每个对话计算消息数量
+    result = []
+    for c in conversations:
+        msg_count = db.query(Message).filter(Message.conversation_id == c.id).count()
+        result.append({
+            "id": c.conversation_id,
+            "title": c.title or "新对话",
+            "created_at": c.created_at.isoformat(),
+            "updated_at": c.updated_at.isoformat(),
+            "message_count": msg_count
+        })
+    
+    return {"conversations": result}
 
 
 @app.get("/api/conversations/latest")
@@ -693,6 +695,26 @@ async def create_conversation(db: Session = Depends(get_db)):
     }
 
 
+@app.get("/api/conversations/{conversation_id}")
+async def get_conversation(conversation_id: str, db: Session = Depends(get_db)):
+    """获取单个对话详情"""
+    conv_service = ConversationService(db)
+    conversation = conv_service.get_conversation(conversation_id)
+    
+    if not conversation:
+        raise HTTPException(status_code=404, detail="会话不存在")
+    
+    msg_count = db.query(Message).filter(Message.conversation_id == conversation.id).count()
+    
+    return {
+        "id": conversation.conversation_id,
+        "title": conversation.title or "新对话",
+        "created_at": conversation.created_at.isoformat(),
+        "updated_at": conversation.updated_at.isoformat(),
+        "message_count": msg_count
+    }
+
+
 @app.get("/api/conversations/{conversation_id}/messages")
 async def get_messages(conversation_id: str, db: Session = Depends(get_db)):
     """获取会话消息"""