DeepSpeed

3e794b17 - Add macOS (MPS) CI workflow and a torch floor check for the MPS accelerator

Add macOS (MPS) CI workflow and a torch floor check for the MPS accelerator Nothing upstream exercised the MPS paths, so regressions could only be caught on a developer's Mac. The new workflow runs the MPS-green unit test subset (fused/CPU Adam, comm staging, config-driven training) on GitHub's arm64 macOS runners, which expose a working MPS device. It cannot interfere with the existing CI: PR triggers are scoped to MPS-relevant paths, the job runs in its own workflow with a hard timeout and concurrency cancellation, and it is not a required check. MPS_Accelerator now fails at construction with a clear message on torch older than 2.3, where the torch.mps memory queries ZeRO depends on do not exist, instead of an AttributeError deep inside the runtime. Signed-off-by: PKUWZP <zhipeng.rainbowserie@gmail.com>