alp CUDA bench

[a10y]

Summary

Adds a benchmark for CUDA execution of ALP arrays, similar to our existing one for bit unpacking.

[codspeed-hq]

Merging this PR will not alter performance

✅ 1163 untouched benchmarks
⏩ 1462 skipped benchmarks¹

---

_{Comparing aduffy/alp-bench-cuda (30a1453) with develop (9fe20c5)}

Footnotes

1. 1462 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[a10y]

Results on GH200

~/vortex$ nvidia-smi
Mon Apr 20 22:09:35 2026
+-----------------------------------------------------------------------------------------+
| NVIDIA-SMI 570.148.08             Driver Version: 570.148.08     CUDA Version: 12.8     |
|-----------------------------------------+------------------------+----------------------+
| GPU  Name                 Persistence-M | Bus-Id          Disp.A | Volatile Uncorr. ECC |
| Fan  Temp   Perf          Pwr:Usage/Cap |           Memory-Usage | GPU-Util  Compute M. |
|                                         |                        |               MIG M. |
|=========================================+========================+======================|
|   0  NVIDIA GH200 480GB             On  |   00000000:DD:00.0 Off |                  Off |
| N/A   35C    P0             74W /  700W |       3MiB /  97871MiB |      0%      Default |
|                                         |                        |             Disabled |
+-----------------------------------------+------------------------+----------------------+

+-----------------------------------------------------------------------------------------+
| Processes:                                                                              |
|  GPU   GI   CI              PID   Type   Process name                        GPU Memory |
|        ID   ID                                                               Usage      |
|=========================================================================================|
|  No running processes found                                                             |
+-----------------------------------------------------------------------------------------+