fix: app freeze on quit (#1804)

* fix: app freeze on quit

* fix: typo in VpnConnection destructor

* add trace info

* add more trace info

* set timelimit for flushDns

* Refactor IpcClient::Interface access logic

* cleanup unused variable

* cleanup trace info

* fix: remove second disconnect from VPN on app close

* this object will be deleted at app close

* Don't terminate VPN thread on Linux

* Revert "Don't terminate VPN thread on Linux"

This reverts commit 20e4ea2d4a.

* disconnect all signals from vpnconnection on exit

* add interruption request on vpnConnectionThread

* use checktimer only for iOS

* disconnect all signals from vpnconnection on exit

* disconnect signals on exit before VPN disconnect

* add disconnectSlots method

* fix: add allow traffic rules on killswitch disable

* wait for response from service before object destroy

* change disconnect from vpn order

* add delay for connection close

* change disconnect method order

* use stop method for protocol disconnecect

* change disconnect method order

* allow dns traffic after app close

* delete tun on disconnect

---------

Co-authored-by: vkamn <vk@amnezia.org>

service/server/router.h

@@ -19,12 +19,12 @@ public:
     static int routeAddList(const QString &gw, const QStringList &ips);
     static bool clearSavedRoutes();
     static int routeDeleteList(const QString &gw, const QStringList &ips);
-    static void flushDns();
+    static bool flushDns();
     static void resetIpStack();
     static bool createTun(const QString &dev, const QString &subnet);
     static bool deleteTun(const QString &dev);
-    static void StartRoutingIpv6();
-    static void StopRoutingIpv6();
+    static bool StartRoutingIpv6();
+    static bool StopRoutingIpv6();
     static bool updateResolvers(const QString& ifname, const QList<QHostAddress>& resolvers);
     static bool restoreResolvers();
 };