Improve: nicer tun info for RESTful api

Let the restful api still get TunConf even when tun is off.
Otherwise the api will return the default values,
instead of the values that actually take effect after enable.

* Due to this problem, yacd changes the displayed value
back to gvisor immediately after the user selects tun stack.

hub/executor/executor.go

@@ -129,7 +129,7 @@ func GetGeneral() *config.General {
 			RedirPort:         ports.RedirPort,
 			TProxyPort:        ports.TProxyPort,
 			MixedPort:         ports.MixedPort,
-			Tun:               listener.GetTunConf(),
+			Tun:               listener.LastTunConf,
 			TuicServer:        listener.GetTuicConf(),
 			ShadowSocksConfig: ports.ShadowSocksConfig,
 			VmessConfig:       ports.VmessConfig,

listener/listener.go

@@ -516,6 +516,7 @@ func ReCreateTun(tunConf LC.Tun, tcpIn chan<- C.ConnContext, udpIn chan<- C.Pack
 	defer func() {
 		if err != nil {
 			log.Errorln("Start TUN listening error: %s", err.Error())
+			tunConf.Enable = false
 			Cleanup(false)
 		}
 	}()