Reflection cleanup, fix il2cpp struct and enum boxing

And temp removing il2cpp IDictionary / IEnumerable helpers, will see what is necessary after knah's rewrite.

src/ExplorerCore.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections;
+using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
 using UnityEngine;