Remove some BUI boilerplate (#28399)

* Remove some BUI boilerplate

- The disposals overrides got removed due to the helper method handling it.
- Replace window creation with CreateWindow helper.
- Fixed some stinky code which would cause exceptions.

* More

* moar

* weh

* done

* More BUIs

* More updates

* weh

* moar

* look who it is

* weh

* merge

* weh

* fixes

Content.Client/Inventory/StrippableBoundUserInterface.cs

@@ -41,7 +41,7 @@ namespace Content.Client.Inventory
         public const string HiddenPocketEntityId = "StrippingHiddenEntity";
 
         [ViewVariables]
-        private readonly StrippingMenu? _strippingMenu;
+        private StrippingMenu? _strippingMenu;
 
         [ViewVariables]
         private readonly EntityUid _virtualHiddenEntity;
@@ -51,33 +51,30 @@ namespace Content.Client.Inventory
             _examine = EntMan.System<ExamineSystem>();
             _inv = EntMan.System<InventorySystem>();
             _cuffable = EntMan.System<SharedCuffableSystem>();
-
-            // TODO update name when identity changes
-            var title = Loc.GetString("strippable-bound-user-interface-stripping-menu-title", ("ownerName", Identity.Name(Owner, EntMan)));
-            _strippingMenu = new StrippingMenu(title, this);
-            _strippingMenu.OnClose += Close;
-
-            // TODO use global entity
-            // BUIs are opened and closed while applying comp sates, so spawning entities here is probably not the best idea.
             _virtualHiddenEntity = EntMan.SpawnEntity(HiddenPocketEntityId, MapCoordinates.Nullspace);
         }
 
         protected override void Open()
         {
             base.Open();
+
+            _strippingMenu = this.CreateWindow<StrippingMenu>();
+            _strippingMenu.OnDirty += UpdateMenu;
+            _strippingMenu.Title = Loc.GetString("strippable-bound-user-interface-stripping-menu-title", ("ownerName", Identity.Name(Owner, EntMan)));
+
             _strippingMenu?.OpenCenteredLeft();
         }
 
         protected override void Dispose(bool disposing)
         {
-            base.Dispose(disposing);
-
-            EntMan.DeleteEntity(_virtualHiddenEntity);
-
             if (!disposing)
                 return;
 
-            _strippingMenu?.Dispose();
+            if (_strippingMenu != null)
+                _strippingMenu.OnDirty -= UpdateMenu;
+
+            EntMan.DeleteEntity(_virtualHiddenEntity);
+            base.Dispose(disposing);
         }
 
         public void DirtyMenu()