gRPC-Web 2.0 compatibility

[tsegismont]

Describe the feature

https://github.com/grpc/grpc-web/releases/tag/2.0.0

gRPC-Web 2.0 is out, the protocol doesn't change (as it seems).

Make sure Vert.x 5 can be used as a backend for gRPC-Web 2.0 client projects.

[zZHorizonZz]

I think this;

Enable support for Editions in protoc-gen-grpc-web.

will be a biggest hurdle as currently jprotoc doesn't really work with editions, and we are using jprotoc for vertx-grpc-protoc-plugin2.

salesforce/grpc-java-contrib#246

[vietj]

I think we could get rid of jprotoc plugin as it does not do that much.

[zZHorizonZz]

Yeah, though do we want to rewrite it completely into our system (At the very least license wise we cannot really use anything from the original), or? I saw that Spring is also using it and they're probably going to be writing their own thing. Maybe we could get in touch with them and do something together, so that there doesn't need to be 20 different alternatives to the same thing?

[zZHorizonZz]

Just a heads up that the issue I raised about us not being able to use editions should be alleviated as we have switched to our custom generator, therefore we can do whatever we want, like working with editions etc.