[feat] 新增 mqttt OnPublish hook

mqtt.go

@@ -43,6 +43,8 @@ type Mqtt interface {
 	OnMessage(g GlobalParams, topic string, retain bool, qos byte) error
 	// 消息被丢弃
 	OnMessageDropped(g GlobalParams, topic string, retain bool, qos byte) error
+	// 原生消息修改
+	OnPublish(g GlobalParams, topic string, retain bool, qos byte, raw []byte) ([]byte, error)
 	// 保留类型消息事件
 	// OnRetainMessage(g GlobalParams, topic string) error
 	// Qos消息完成事件