akka-grpc 2.3.0 is now available under Apache license

More than 3 years since release

https://github.com/akka/akka-grpc/releases/tag/v2.3.0

We may not want all the changes. Pekko gRPC has always supported Scala 3, for instance. Better if any changes for Pekko gRPC can be justified by need as opposed to blindly copying everything.

Start by reading the linked akka-grpc 2.3.0 release notes and comparing its changes with the current Pekko gRPC project. Identify which changes are relevant to Pekko gRPC, record the need for each, and consider the work complete when the justified changes are clearly identified rather than copied wholesale.

Written by the indexing model from the issue text.