fix(Facade): use extension method to set enum value

The SetSelectionMethod method now uses the Zinnia EnumExtensions
helper method to set the value of the enum by the index instead of
repeating the same logic.

Runtime/SharedResources/Scripts/PointerFacade.cs

@@ -9,6 +9,7 @@
     using Zinnia.Action;
     using Zinnia.Cast;
     using Zinnia.Data.Attribute;
+    using Zinnia.Extension;
     using Zinnia.Pointer;
     using Zinnia.Rule;
 
@@ -119,7 +120,7 @@ public enum SelectionType
         /// <param name="selectionMethodIndex">The index of the <see cref="SelectionType"/>.</param>
         public virtual void SetSelectionMethod(int selectionMethodIndex)
         {
-            SelectionMethod = (SelectionType)Mathf.Clamp(selectionMethodIndex, 0, System.Enum.GetValues(typeof(SelectionType)).Length);
+            SelectionMethod = EnumExtensions.GetByIndex<SelectionType>(selectionMethodIndex);
         }
 
         /// <summary>