Expose flashinfer_cute_dsl as fp8 gemm backend

[IwakuraRein]

Motivation

Expose flashinfer_cute_dsl as fp8 gemm backend since it achieves better perf for muse glimmer on B200/300.

PR dependency: #34262.

Modifications

Accuracy Tests

Speed Tests and Profiling

Benchmark Muse Glimmer on a single B300, ISL 2048, OSL 256:

Flashinfer benchmark on a single B300 with Muse Glimmer shape

N=6656, K=19968

M	cutlass (TFLOPs/s)	cute-dsl (TFLOPs/s)
1	6.312	8.555
32	208.153	256.573
64	415.487	494.538
128	817.889	982.648
256	1446.592	1818.284
512	2224.931	2624.488
1024	2708.906	3201.373
2048	2838.883	3499.666
4096	3519.589	3449.986
8192	3403.057	3193.448

N=19968, K=6656

M	cutlass (TFLOPs/s)	cute-dsl (TFLOPs/s)
1	6.775	7.504
32	224.885	244.536
64	448.619	498.479
128	895.739	1002.112
256	1463.501	1680.373
512	2261.627	2641.604
1024	3029.742	3146.874
2048	3539.739	3382.431
4096	3710.748	3601.933
8192	3635.707	3376.387

Checklist

• Format your code according to the Format code with pre-commit.
• Add unit tests according to the Run and add unit tests.
• Update documentation according to Write documentations.
• Provide accuracy and speed benchmark results according to Test the accuracy and Benchmark the speed.
• Follow the SGLang code style guidance.

Review and Merge Process

1. Ping Merge Oncalls to start the process. See the PR Merge Process.
2. Get approvals from CODEOWNERS and other reviewers.
3. Trigger CI tests with comments or contact authorized users to do so.
   • Common commands include /tag-and-rerun-ci, /tag-run-ci-label, /rerun-failed-ci
4. After green CI and required approvals, ask Merge Oncalls or people with Write permission to merge the PR.

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CI States

Latest PR Test (Base): ❌ Run #31618178019
Latest PR Test (Extra): ❌ Run #31618177806

[mmangkad]

Hi @IwakuraRein, this is actually already being worked on in #34042

[IwakuraRein]

Close due to duplicating #34042