refactor: update dpsk fused_moe test [2] (#2097)

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## 📌 Description

Add shuffling and blockmajorK layout in dpskv3 fused_moe fp8_blockscaled
tests.

## 🔍 Related Issues

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## 🧪 Tests

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<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit

* **Tests**
* Expanded MoE test suite with per-expert weight shuffling, optional
block-layout conversion, selectable weight-processing modes, and dynamic
kernel flags.
* Added a reference FP8 block-scale validation path and centralized
accuracy checks for clearer correctness verification.
* **Refactor**
* Centralized test utilities: quantization mode and test-skip logic
moved into shared helpers for consistent gating across MoE tests.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

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Co-authored-by: Zihao Ye <[email protected]>

Author: yyihuang