Improve vector and matrix performance and add swizzle support to .net build-int VectorX type.

Misaki.HighPerformance.Mathematics.CodeGen/Generators/GeneratorBase.cs

@@ -19,6 +19,12 @@ namespace Misaki.HighPerformance.Mathematics.CodeGen.Generators
             this.typeInfo = typeInfo;
             sourceBuilder.Clear();
 
+            var message = Validation();
+            if (message != null)
+            {
+                return message;
+            }
+
             Initialize();
 
             GenerateHeader();
@@ -45,6 +51,11 @@ namespace Misaki.HighPerformance.Mathematics.CodeGen.Generators
 #endregion");
         }
 
+        protected virtual string? Validation()
+        {
+            return null;
+        }
+
         protected virtual void Initialize()
         {
         }