Rework metadata struct loading to use new struct versioning

VersionedSerialization/Attributes/AlignedAttribute.cs

@@ -1,6 +0,0 @@
-namespace VersionedSerialization.Attributes;
-
-#pragma warning disable CS9113 // Parameter is unread.
-[AttributeUsage(AttributeTargets.Property | AttributeTargets.Field)]
-public class AlignedAttribute(int alignment) : Attribute;
-#pragma warning restore CS9113 // Parameter is unread.

VersionedSerialization/Attributes/NativeIntegerAttribute.cs

@@ -0,0 +1,3 @@
+namespace VersionedSerialization.Attributes;
+
+public class NativeIntegerAttribute : Attribute;