Add Linux WI-FI state support

Support monitoring WIFI state on Linux through:
- NetworkManager (D-Bus)
- IWD (D-Bus)
- wpa_supplicant (control socket)
- ConnMan (D-Bus)

experimental/libbox/service.go

@@ -111,7 +111,7 @@ func (s *BoxService) Close() error {
 }
 
 func (s *BoxService) NeedWIFIState() bool {
-	return s.instance.Router().NeedWIFIState()
+	return s.instance.Network().NeedWIFIState()
 }
 
 var (
@@ -224,6 +224,10 @@ func (w *platformInterfaceWrapper) ClearDNSCache() {
 	w.iif.ClearDNSCache()
 }
 
+func (w *platformInterfaceWrapper) UsePlatformWIFIMonitor() bool {
+	return true
+}
+
 func (w *platformInterfaceWrapper) ReadWIFIState() adapter.WIFIState {
 	wifiState := w.iif.ReadWIFIState()
 	if wifiState == nil {