Add support for protobuf-language-server

[ahakanbaba]

Name: protobuf-language-server
URL: https://github.com/lasorda/protobuf-language-server

This is a language server protocol for proto files. Proto files have some support in ale https://github.com/dense-analysis/ale/tree/898638abe586999d38a1f5b54505e2b351a3f80b/ale_linters/proto
Adding support for this language server would be very useful, helpful.

If this looks OK, I may spend some time for adding the support.

[ahakanbaba]

@hsanson Would there be any interest in this capability. If the maintainers are open to it I could take a stab at it.