refactor qwen moe code, use communicator to support tp+dp

[yizhang2077]

Motivation

refactor qwen2/qwen3moe tp+dp code, use communicator in #6321

Modifications

Checklist

• Format your code according to the Code Formatting with Pre-Commit.
• Add unit tests as outlined in the Running Unit Tests.
• Update documentation / docstrings / example tutorials as needed, according to Writing Documentation.
• Provide throughput / latency benchmark results and accuracy evaluation results as needed, according to Benchmark and Profiling and Accuracy Results.
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[fzyzcjy]

LGTM as long as tests pass, and only a few small nits