If I use xds at my Java codebase, there is only two options: 1. copy xds *.proto to my codebase, like [grpc-java](https://github.com/grpc/grpc-java/tree/v1.51.0/xds/third_party/xds/src/main/proto/xds) 2. generate java stab and put it to maven repo. So, I think we could release official maven package? like `io.cncf.xds:xds:3.0.0`?