docs: update Ascend NPU documentation

[UsernameFull]

Summary

This PR updates Ascend NPU Dockerfiles, examples, CI, and documentation to align with the current FSDP2 + vLLM-Ascend path.

Main changes:

• Update A2/A3 Docker dependencies:
  • CANN 9.0.0
  • PyTorch 2.9.0
  • vLLM / vLLM-Ascend 0.18.0
  • triton-ascend 3.2.1
• Add Atlas A5 installation notes:
  • torch 2.10
  • vLLM v0.20.2
  • vLLM-Ascend main
  • COMPILE_CUSTOM_KERNELS=1
• Update Ascend NPU documentation in English and Chinese.
• Add Chinese RLVR documentation.
• Switch the Ascend RLVR launcher to qwen3_30b_rlvr_fsdp2.
• Remove the old DPO DeepSpeed launcher.
• Remove DeepSpeed installation and related tests from NPU CI.

Scope

This PR only affects Ascend NPU Dockerfiles, documentation, examples, and NPU CI.