Expose controlplane.v1.CASBackendService/Update endpoint as REST #2568
Description
Currently, the controlplane.v1.CASBackendService/Update endpoint is only available via gRPC. It would be beneficial to expose this functionality as a REST endpoint as well. This would allow containers to interact with the service using standard tools like curl or wget, eliminating the need to install additional tools such as buf or grpcurl. It would also make it easier to use default container images without customization.