utils/ips/dynamic_ip_port: drop unused json/v2 marshaler

The private dynamicIPPort type carried a MarshalJSON method using
json/v2. No consumer of DynamicIPPort in the node module relied on the
JSON path — the public IPPort/IPDesc types in ip_port.go retain their
JSON methods for the external node-info HTTP API. Drop the unused
internal marshaler; one path for IP serialization, on the boundary
that owns the wire shape.

utils/ips/dynamic_ip_port.go

@@ -1,11 +1,9 @@
 // Copyright (C) 2019-2025, Lux Industries Inc. All rights reserved.
 // See the file LICENSE for licensing terms.
 
-
 package ips
 
 import (
-	"github.com/go-json-experiment/json"
 	"net"
 	"sync"
 )
@@ -48,10 +46,3 @@ func (i *dynamicIPPort) SetIP(ip net.IP) {
 
 	i.ipPort.IP = ip
 }
-
-func (i *dynamicIPPort) MarshalJSON() ([]byte, error) {
-	i.lock.RLock()
-	defer i.lock.RUnlock()
-
-	return json.Marshal(i.ipPort)
-}