Chenguang Li

Add Ascend NPU as a backend

4

### Description :rocket:Ascend is a full-stack AI computing infrastructure for industry applications and services based on Huawei Ascend processors and software. For more information about Ascend, see [Ascend Community](https://www.hiascend.com/en/). [CANN](https://www.hiascend.com/en/software/cann)...

### Why is this PR needed? Add support for the MUL_MAT_ID operator required by MOE models. ### Op Test ``` Backend 1/2: CANN0 ggml_backend_cann_context: device 0 async operator submission is...

[Refactor]Rename NCCL-related items to comm_backend

5

## Why are these changes needed? ### Background This PR is a follow-up to [#51032](https://github.com/ray-project/ray/pull/51032), which introduced multi-device support in the Compiled Graph by leveraging CUDA's NCCL backend for efficient...