apache/dubbo — reverse-engineered prompt

Build me a Java based RPC and microservice framework similar to Apache Dubbo. I want developers to define a service, start a provider, and call it from a consumer without writing a lot of plumbing. It should support simple RPC calls, REST style calls, and a gRPC compatible Triple style protocol if practical.

Include service discovery through a registry like Zookeeper or Nacos, basic routing and traffic control, config that can be changed without rebuilding, and hooks for metrics, tracing, and security.

Please include a Spring Boot starter style example and a lightweight local example, with clear commands to build and test. Add a small demo service so someone can run the provider and consumer on their machine and see the call work. Look up current docs online if you need to.