[rollout, vllm] fix: name change for compilation level

[HollowMan6]

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Refer to: vllm-project/vllm@96b9aa5

There's a name change from compilation level to compilation mode in recent vLLM version, this PR fixes this issue and make it backward compatible as well.

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[gemini-code-assist]

Code Review

This pull request correctly addresses a breaking change in a recent vllm version by introducing backward compatibility for the change from compilation_level to compilation_mode. The use of a try-except block for feature detection is a robust approach. I have one suggestion to refactor a small piece of duplicated code to improve maintainability.

[HollowMan6]

/gemini review

[gemini-code-assist]

Code Review

This PR addresses a name change from CompilationLevel to CompilationMode in recent vLLM versions, ensuring backward compatibility. The code modifications involve adding a try-except block to handle potential ImportError when importing CompilationMode and adjusting the compilation_config dictionary accordingly. The review focuses on ensuring the correctness of the backward compatibility implementation and the clarity of the code.