add hide/unhide for renderkey

ViewModels/GlobalSettingsViewModel.cs

@@ -8,6 +8,7 @@ namespace UnifiedFarmLauncher.ViewModels
         private readonly ConfigService _configService;
         private string _sheepItUsername = string.Empty;
         private string _sheepItRenderKey = string.Empty;
+        private bool _isRenderKeyVisible = false;
 
         public GlobalSettingsViewModel(ConfigService configService)
         {
@@ -27,6 +28,12 @@ namespace UnifiedFarmLauncher.ViewModels
             set => SetAndRaise(ref _sheepItRenderKey, value);
         }
 
+        public bool IsRenderKeyVisible
+        {
+            get => _isRenderKeyVisible;
+            set => SetAndRaise(ref _isRenderKeyVisible, value);
+        }
+
         private void LoadSettings()
         {
             var config = _configService.Load();