Use C# 12 [] syntax for empty ToonPropertyAccessor array

Replaced Array.Empty<ToonPropertyAccessor>() with the new C# 12 collection expression [] for initializing the Properties field as an empty array, resulting in more concise and modern code.

AyCode.Core/Serializers/Toons/AcToonSerializer.ToonTypeMetadata.cs

@@ -53,7 +53,7 @@ public static partial class AcToonSerializer
             }
             else
             {
-                Properties = Array.Empty<ToonPropertyAccessor>();
+                Properties = [];
             }
         }
     }