[cpyrt] Detect enum arguments by type in overload priority

[aaronj0]

GetPriority() deprioritizes enum arguments so that a competing integer overload wins, since C++ has no implicit int->enum conversion, but it detected them with IsEnumScope(GetScope(name)). GetScope does not resolve an enum name to a scope, so the penalty never applied. Query the argument type with IsEnumType as well, per the existing FIXME.

[guitargeek]

Thanks, this goes in the right direction! pick(2) now returns 2, penalty fires via IsEnumType(GetMethodArgType(...)). One remaining problem though: the penalty is argument-agnostic, so pick(Color.Green) now returns 2: previously 1, and C++ overload resolution would also give 1. An enum object is an exact match for the enum overload.

I think this is a behavioral regression that needs to be fixed and locked in to the unit test.