refactor vpn settings

fix: nekoray_core freedom udp loopback

feat: copy custom config

fmt/AbstractBean.hpp

@@ -15,6 +15,7 @@ namespace NekoRay::fmt {
         QStringList env;
         QStringList arguments;
         QString error;
+        QString config_export;
     };
 
     class AbstractBean : public JsonStore {
@@ -38,6 +39,8 @@ namespace NekoRay::fmt {
 
         [[nodiscard]] virtual QString DisplayName();
 
+        virtual QString DisplayCoreType() { return software_core_name; };
+
         virtual QString DisplayType() { return {}; };
 
         virtual QString DisplayTypeAndName();