Revert "Fix: Correct file variable handling for custom tools in workflow (#24061)

api/core/workflow/nodes/tool/tool_node.py

                     json.append(message.message.json_object)
             elif message.type == ToolInvokeMessage.MessageType.LINK:
                 assert isinstance(message.message, ToolInvokeMessage.TextMessage)
-
-                if message.meta:
-                    transfer_method = message.meta.get("transfer_method", FileTransferMethod.TOOL_FILE)
-                else:
-                    transfer_method = FileTransferMethod.TOOL_FILE
-
-                tool_file_id = message.message.text.split("/")[-1].split(".")[0]
-
-                with Session(db.engine) as session:
-                    stmt = select(ToolFile).where(ToolFile.id == tool_file_id)
-                    tool_file = session.scalar(stmt)
-                    if tool_file is None:
-                        raise ToolFileError(f"Tool file {tool_file_id} does not exist")
-
-                mapping = {
-                    "tool_file_id": tool_file_id,
-                    "type": file_factory.get_file_type_by_mime_type(tool_file.mimetype),
-                    "transfer_method": transfer_method,
-                    "url": message.message.text,
-                }
-
-                file = file_factory.build_from_mapping(
-                    mapping=mapping,
-                    tenant_id=self.tenant_id,
-                )
-                files.append(file)
-
                 stream_text = f"Link: {message.message.text}\n"
                 text += stream_text
                 yield RunStreamChunkEvent(chunk_content=stream_text, from_variable_selector=[node_id, "text"])