参考jbpm，进行定制开发的工作流引擎框架。支持的特性包括配置式开发、多版本管理、实现会签等复杂功能。具体的设计文档将参考上传的设计文档。-Reference jbpm workflow engine fr a mework for custom development. Including configuration and development, version management, and countersigned and other complex functions. The s