[Bugfix] Refactor to support DP parallel in R3

[xhx1022]

Fix a bug introduced during the DP parallel for R3(#28284).

[github-actions]

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[gemini-code-assist]

Code Review

This pull request effectively addresses a bug in data parallelism for routed experts. The changes correctly introduce rank-specific shared memory resources, preventing race conditions between data-parallel ranks. The logic for handling sharded data within the capture method is sound and properly slices tensors based on the data-parallel rank. Additionally, the refactoring to use the more general VllmConfig is a good improvement for code clarity and maintainability. Overall, the changes are correct and well-implemented.

[xhx1022]

@Mergifyio rebase

[mergify]

rebase

✅ Branch has been successfully rebased

[xhx1022]

@youkaichao