扩展点重构

1、经过对dubboSPI的了解，对于dubbo的SPI机制的封装希望后续可以独立出来单独使用，某些企业的项目可能只想集成SPI的方式进行扩展
2、dubbo在SPI的进行依赖注入时，好像只能根据属性名称注入，某些场景下一个接口多个实现，此时实现在spring容器中的bean名称是自定义，此时可能会出现属性名与bean名称不一致导致找不到spring容器里面的bean，从而注入失败

No files, entry points, or tests are named. Start by locating the Dubbo SPI implementation and its Spring-container dependency-injection coverage, then clarify whether standalone extraction and custom bean-name resolution are both in scope. Done requires an agreed design and corresponding tests.

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