Support w8a8 block_fp8_matmul from generated kernel

[wenscarl]

A lightweight integration layer to enable w8a8_block_fp8_matmul support using the generated block FP8 matrix multiplication kernels.

Note: This kernel requires the scale factor to have a shape of [K/128, M], which is incompatible with the Triton equivalent. To resolve this, an implicit transpose is applied.

Performance Comparison of DeepSeek v3 on blackwell: Generated Kernel vs. Triton
Eager Mode
generated kernel: Throughput: 0.10 requests/s, 114.93 total tokens/s, 101.32 output tokens/s
Triton: Throughput: 0.09 requests/s, 103.54 total tokens/s, 91.28 output tokens/s
Graph Mode
generated kernel: Throughput: 0.14 requests/s, 162.16 total tokens/s, 142.97 output tokens/s
Triton: Throughput: 0.11 requests/s, 126.15 total tokens/s, 111.22 output tokens/s

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[mergify]

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

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

[hmellor]

Closing as the w8a8 block linear architecture has since been refactored (#33047, #33892, #33893). The generated kernels would need to be reworked to fit the new framework. Feel free to open a fresh PR if you'd like to integrate them. Thanks for the contribution!