refactor: message entity

protocol/bt/peer/message/msg_interested.go

@@ -1,24 +1,14 @@
 package message
 
-// choke: <len=0001><id=0>
+// choke: <len=0001><id=2>
 type Interested struct {
-	Message
+	*base
 }
 
 func NewInterested() *Interested {
 	return &Interested{
-		Message{
-			Length: 1,
-			ID:     IdInterested,
+		base: &base{
+			id: IdInterested,
 		},
 	}
 }
-
-func (c *Interested) Encode() []byte {
-	return c.Message.Encode()
-}
-
-func (c *Interested) Decode(buf []byte) Serialize {
-	c.Message.Decode(buf)
-	return c
-}