[CPU] Add CPU FP8 W8A8 linear/MoE support

[yuwenzho]

Purpose

Support FP8 W8A8 Linear and MoE for Intel DMR CPUs.

Test Plan

Kernel tests:

• python -m pytest tests/kernels/moe/test_cpu_quant_fused_moe.py -v
• python -m pytest tests/kernels/quantization/test_cpu_fp8_scaled_mm.py -v

Validated models:

• RedHatAI/Meta-Llama-3.1-8B-Instruct-FP8-dynamic (dense, per-channel weight / dynamic per-token act): CPUFP8W8A8ScaledMMLinearKernel
• Qwen/Qwen3.5-35B-A3B-FP8 (MoE, block-wise 128x128 weight / dynamic act): CPUFp8W8A8BlockScaledMMKernel, CPUExpertsFp8W8A8
• deepseek-ai/DeepSeek-R1 (MoE + MLA, block-wise 128x128 weight / dynamic act): CPUFp8W8A8BlockScaledMMKernel, CPUExpertsFp8W8A8

Test Result

python -m pytest tests/kernels/moe/test_cpu_quant_fused_moe.py -v : 185 passed
python -m pytest tests/kernels/quantization/test_cpu_fp8_scaled_mm.py -v: 190 passed

E2E Qwen/Qwen3.5-35B-A3B-FP8 gsm8k on DMR: 0.802

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• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model.

[mergify]

This pull request has merge conflicts that must be resolved before it can be
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[mergify]

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[mergify]

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[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @yuwenzho.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[claude]

Claude Code Review

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[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @yuwenzho.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[bigPYJ1151]

Thanks @yuwenzho Overall looks great. I just have some little tips, please check.

[bigPYJ1151]

/ci run

[github-actions]

❌ This PR is 90 commits behind upstream main. Your branch must contain every commit currently on upstream main. No new CI build was started. Merge or rebase onto the latest main, then rerun /ci run. To test this branch at your own risk, use /ci run --allow-stale.

[github-actions]

✅ Triggered Buildkite CI #89805 for commit 85d9c37f42c0.

⚠️ This PR is 90 commits behind upstream main. Running CI at your own risk because --allow-stale was requested; outdated CI configuration may cause failures. Before merging, merge or rebase onto the latest main, then rerun /ci run on the latest PR commit.

[bigPYJ1151]

/ci run

[github-actions]

❌ This PR is 1 commit behind upstream main. Your branch must contain every commit currently on upstream main. No new CI build was started. Merge or rebase onto the latest main, then rerun /ci run. To test this branch at your own risk, use /ci run --allow-stale.

[bigPYJ1151]

/ci run

[github-actions]

✅ Triggered Buildkite CI #89807 for commit b9d8d59146ae.

[louie-tsai]

@louie-tsai DMR