v3 refactor (#1868)

* Move to v3

Co-authored-by: Ben Toogood <bentoogood@gmail.com>

server/mucp/rpc_event.go

@@ -0,0 +1,38 @@
+package mucp
+
+import (
+	"github.com/micro/go-micro/v3/broker"
+	"github.com/micro/go-micro/v3/transport"
+)
+
+// event is a broker event we handle on the server transport
+type event struct {
+	err     error
+	message *broker.Message
+}
+
+func (e *event) Ack() error {
+	// there is no ack support
+	return nil
+}
+
+func (e *event) Message() *broker.Message {
+	return e.message
+}
+
+func (e *event) Error() error {
+	return e.err
+}
+
+func (e *event) Topic() string {
+	return e.message.Header["Micro-Topic"]
+}
+
+func newEvent(msg transport.Message) *event {
+	return &event{
+		message: &broker.Message{
+			Header: msg.Header,
+			Body:   msg.Body,
+		},
+	}
+}