Create shader converters as XCFrameworks.
Don't create shader converters as fat libs, dylibs, or regular frameworks.
Rename create_xcframework.sh to create_xcframework_func.sh.
Use separate MoltenVK packaging scripts for one or all OS's.
Add package_one_os.sh.
Remove package_shader_converter_lib.sh.
Remove redundant GLSL shader converter dependencies in MoltenVK packaging targets.