Greatly simplify handling numerical eval values, using std::variant

src/UserData/UserDataCollections/UserDataCollectionRangeIterator.hpp

@@ -18,7 +18,7 @@ namespace Porygon::UserData{
         }
 
         const Evaluation::EvalValue* GetCurrent() final{
-            return new Evaluation::IntegerEvalValue(_current);
+            return new Evaluation::NumericEvalValue(static_cast<int64_t>(_current));
         }
         bool MoveNext() final{
             _current ++;