implement grpc gateway and addl handler support

pkg/srv/grpc/opts/config.go

@@ -19,7 +19,9 @@ type AppGRPC struct {
 	UnaryInterceptors  []grpc.UnaryServerInterceptor
 	StreamInterceptors []grpc.StreamServerInterceptor
 	GRPCOpts           []grpc.ServerOption
+	GRPCDialOpts       []grpc.DialOption // Map ServerOptions to DialOpts for GRPC Gateway support
 	GRPCDone           <-chan error
+	gatewayMux         *runtime.ServeMux
 }
 
 type GRPCService struct {
@@ -28,3 +30,11 @@ type GRPCService struct {
 	Service             any                                                                // Implementation of GRPCService.Type (ptr)
 	GwRegistrationFuncs []func(context.Context, *runtime.ServeMux, *grpc.ClientConn) error // Gateway regustration handler funcs
 }
+
+func (a *AppGRPC) SetGatewayMux(mux *runtime.ServeMux) {
+	a.gatewayMux = mux
+}
+
+func (a *AppGRPC) GetGatewayMux() *runtime.ServeMux {
+	return a.gatewayMux
+}