Context menu UI backend refactor & better UX (#13318)

closes https://github.com/space-wizards/space-station-14/issues/9209

Content.Client/ContextMenu/UI/EntityMenuPresenterGrouping.cs

@@ -1,16 +1,17 @@
 using Content.Shared.IdentityManagement;
 using Robust.Client.GameObjects;
 using System.Linq;
+using Robust.Client.UserInterface.Controllers;
 
 namespace Content.Client.ContextMenu.UI
 {
-    public sealed partial class EntityMenuPresenter : ContextMenuPresenter
+    public sealed partial class EntityMenuUIController
     {
         public const int GroupingTypesCount = 2;
         private int GroupingContextMenuType { get; set; }
         public void OnGroupingChanged(int obj)
         {
-            Close();
+            _context.Close();
             GroupingContextMenuType = obj;
         }