The number of lods are now properly loaded from the model data, and race
is checked by checking for the existence of race-specific models (I
think this is the current best way?).
Also, magic_enum is added as a dependency for some enum magic involving
enumerating Race.
Qt5 for macOS can actually use the same code as on Linux/Win, but
apparently no one wants to build it with Vulkan support. Instead, we
spawn a standalone SDL2 window.
