[iOS GPU] Add Metal API availability check (#57663)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/57663
Detail error messages when shader compilation fails.
ghstack-source-id: 128282408
Test Plan: CI
Reviewed By: linbinyu
Differential Revision: D28247966
fbshipit-source-id: 2c8ae575acbb197048c1edde28674ab69f008751
