[1/N][Platform] Refactor check_and_update_config

[wangxiyuan]

check_and_update_config function become large and hard for maintain.

This PR refactor this function.

1. Add more comment for each step
2. move compilation related code to compilation module
3. remove ueless _set_cudagraph_sizes logic.

• vLLM version: v0.11.0rc3
• vLLM main: vllm-project/vllm@releases/v0.11.1

[github-actions]

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[gemini-code-assist]

Code Review

This pull request refactors the check_and_update_config function by extracting compilation-related logic into a new vllm_ascend/compilation/utils.py file. This improves code organization and readability in vllm_ascend/platform.py. The changes are well-structured. However, I found a critical issue in the newly added _update_aclgraph_sizes function that could lead to a ZeroDivisionError or an IndexError, causing the application to crash. I have provided a code suggestion to fix these issues and improve the sampling logic.

[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.