Extension Classes: Enums/Integer constants missing

[dazKind]

via https://github.com/godotengine/godot-headers/blob/0c542567a900e474dcf6312cc97500168bec0c74/godot/gdnative_interface.h#L540

[dazKind]

Fix & Rewrite: https://github.com/dazKind/hxgodot-cpp/blob/main/src/godot/macros/ArgumentMacros.hx#L34

[dazKind]

Managed return types are working