[Core] Remove V0 executors

[njhill]

vllm.v1.executors.Executor becomes the base executor class.

[gemini-code-assist]

Code Review

This pull request is a significant and well-executed refactoring that removes the V0 executors and consolidates the executor logic around the new vllm.v1.executor.Executor base class. The changes are extensive, touching many files to update imports, remove obsolete code and environment variables (VLLM_USE_RAY_SPMD_WORKER, VLLM_USE_RAY_COMPILED_DAG), and align with the new V1 executor API. The new structure is more logical and simplifies the codebase. I have reviewed the changes and found no critical or high-severity issues. The refactoring appears to be consistent and correct across the entire pull request.

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

ℹ️ About Codex in GitHub

Codex has been enabled to automatically review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

When you sign up for Codex through ChatGPT, Codex can also answer questions or update the PR, like "@codex address that feedback".