基本完成，舒适性修补

backend/api/routes/chatsRoute.py

@@ -134,3 +134,45 @@ async def update_table_data(role_name: str, chat_name: str, table_update: dict):
 		raise HTTPException(status_code=404, detail=str(e))
 	except Exception as e:
 		raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.post("/{role_name}/{chat_name}/branch", status_code=status.HTTP_201_CREATED)
+async def branch_chat(role_name: str, chat_name: str, branch_data: dict):
+	"""
+	创建聊天分支
+	
+	复制当前楼层及之前的所有内容到一个新的聊天记录
+	
+	Args:
+		role_name: 角色名称
+		chat_name: 原聊天名称
+		branch_data: {
+			"target_floor": int,  # 目标楼层（包含该楼层及之前的内容）
+			"new_chat_name": str  # 新聊天名称（可选，默认自动生成）
+		}
+	
+	Returns:
+		{
+			"success": bool,
+			"new_chat_name": str,
+			"message_count": int
+		}
+	"""
+	try:
+		target_floor = branch_data.get("target_floor")
+		new_chat_name = branch_data.get("new_chat_name")
+		
+		if target_floor is None:
+			raise HTTPException(status_code=400, detail="缺少 target_floor 参数")
+		
+		# 调用服务层创建分支
+		result = chat_service.create_branch(role_name, chat_name, target_floor, new_chat_name)
+		
+		return result
+		
+	except FileNotFoundError as e:
+		raise HTTPException(status_code=404, detail=str(e))
+	except ValueError as e:
+		raise HTTPException(status_code=400, detail=str(e))
+	except Exception as e:
+		raise HTTPException(status_code=500, detail=f"创建分支失败: {str(e)}")