[dev] Fix HybridEP token equalization under torch.compile without CUDA graphs

[HaochenYuan]

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What does this PR do?

This PR fixes HybridEP token-count equalization when using torch.compile without CUDA Graphs. Previously, torch.compiler.is_compiling() incorrectly implied that inputs were statically padded, causing ranks with different token counts to skip the group-wide MAX.
The fix derives static token equality from the THD padding configuration: only max-padded inputs skip the collective, while unpadded or alignment-only inputs are equalized across ranks.

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[xiaoyao0115]

lgtm