fix: 文件下载接口无文件响应json

src/framework/utils/file/file.go

@@ -177,13 +177,13 @@ func ReadUploadFileStream(filePath, headerRange string) (map[string]any, error)
 		"range":     "",
 		"chunkSize": 0,
 		"fileSize":  0,
-		"data":      nil,
+		"data":      []byte{},
 	}
 
 	// 文件大小
 	fileSize := getFileSize(fileAsbPath)
 	if fileSize <= 0 {
-		return result, nil
+		return result, fmt.Errorf("file does not exist")
 	}
 	result["fileSize"] = fileSize