feat: Support for multiple rpc service generation and rpc grouping (#1972)

* Add group & compatible flag

* Add group & compatible flag

* Support for multiple rpc service generation and rpc grouping

* Support for multiple rpc service generation and rpc grouping

* Format code

* Format code

* Add comments

* Fix unit test

* Refactor function name

* Add example & Update grpc readme

* go mod tidy

* update mod

* update mod

tools/goctl/rpc/cli/zrpc.go

@@ -95,6 +95,7 @@ func ZRPC(_ *cobra.Command, args []string) error {
 	}
 
 	var ctx generator.ZRpcContext
+	ctx.Multiple = VarBoolMultiple
 	ctx.Src = source
 	ctx.GoOutput = goOut
 	ctx.GrpcOutput = grpcOut