Improve performance on struct.unpack (#1817)

* Improve performance on struct

* Fix some struct issues

* Remove array overloads

* Clean up unpack_iterator

* Fix packaging on .NET 9 SDK

Author: slozier

Directory.Build.props

@@ -121,7 +121,7 @@
 
   <!-- Release -->
   <PropertyGroup Condition="'$(Configuration)' == 'Release'">
-    <DebugSymbols>false</DebugSymbols>
+    <DebugSymbols>true</DebugSymbols>
     <DebugType>portable</DebugType>
     <Optimize>true</Optimize>
     <CheckForOverflowUnderflow>false</CheckForOverflowUnderflow>

Src/IronPython.Modules/_ctypes/_ctypes.cs

@@ -688,10 +688,6 @@ private static IntPtr GetHandleFromObject(object dll, string errorMsg) {
             return intPtrHandle;
         }
 
-        private static void ValidateArraySizes(ArrayModule.array array, int offset, int size) {
-            ValidateArraySizes(array.__len__() * array.itemsize, offset, size);
-        }
-
         private static void ValidateArraySizes(int arraySize, int offset, int size) {
             if (offset < 0) {
                 throw PythonOps.ValueError("offset cannot be negative");