fix: reorder imports in base_chat_node.py for better organization

Author: liuruibin

apps/application/flow/step_node/ai_chat_step_node/impl/base_chat_node.py

@@ -12,26 +12,27 @@
 import time
 from functools import reduce
 from imghdr import what
-from typing import List, Dict
+from typing import Dict, List
 
-from django.db.models import QuerySet
-from django.utils.translation import gettext as _
-from langchain_core.messages import BaseMessage, AIMessage, HumanMessage, SystemMessage
-
-from application.flow.common import WorkflowMode
-from application.flow.i_step_node import NodeResult, INode
-from application.flow.step_node.ai_chat_step_node.i_chat_node import IChatNode
-from application.flow.tools import Reasoning, mcp_response_generator, get_tools
-from application.models import Application, ApplicationApiKey, ApplicationAccessToken
 from common.exception.app_exception import AppApiException
+from common.utils.logger import maxkb_logger
 from common.utils.rsa_util import rsa_long_decrypt
 from common.utils.shared_resource_auth import filter_authorized_ids
 from common.utils.tool_code import ToolExecutor
-from common.utils.logger import maxkb_logger
+from django.db.models import QuerySet
+from django.utils.translation import gettext as _
+from knowledge.models import File
+from langchain_core.messages import AIMessage, BaseMessage, HumanMessage, SystemMessage
 from models_provider.models import Model
 from models_provider.tools import get_model_credential, get_model_instance_by_model_workspace_id
 from tools.models import Tool, ToolType
 
+from application.flow.common import WorkflowMode
+from application.flow.i_step_node import INode, NodeResult
+from application.flow.step_node.ai_chat_step_node.i_chat_node import IChatNode
+from application.flow.tools import Reasoning, get_tools, mcp_response_generator
+from application.models import Application, ApplicationAccessToken, ApplicationApiKey
+
 
 def _write_context(node_variable: Dict, workflow_variable: Dict, node: INode, workflow, answer: str,
                    reasoning_content: str):