Chore: improve code architecture

adapters/outbound/shadowsocks.go

@@ -2,6 +2,7 @@ package adapters
 
 import (
 	"bytes"
+	"encoding/json"
 	"fmt"
 	"net"
 	"strconv"
@@ -71,6 +72,12 @@ func (ss *ShadowSocks) Generator(metadata *C.Metadata) (adapter C.ProxyAdapter,
 	return &ShadowsocksAdapter{conn: c}, err
 }
 
+func (ss *ShadowSocks) MarshalJSON() ([]byte, error) {
+	return json.Marshal(map[string]string{
+		"type": ss.Type().String(),
+	})
+}
+
 func NewShadowSocks(option ShadowSocksOption) (*ShadowSocks, error) {
 	server := net.JoinHostPort(option.Server, strconv.Itoa(option.Port))
 	cipher := option.Cipher