feat(prover): Add gpu_checker binary

[yorik]

What ❔

Add gpu_checker binary.

Why ❔

To quickly test if GPU is functioning properly.

Checklist

• PR title corresponds to the body of PR (we generate changelog entries from PRs).
• Tests for the changes have been added / updated.
• Documentation comments have been added / updated.
• Code has been formatted via zkstack dev fmt and zkstack dev lint.

[EmilLuta]

Looks overall good. Left a bunch of comments. I'm wondering, does it make to have 2 modes -- 1 in which you generate everything from scratch & one where you only run the GPU (with WVG already provided)? I'm thinking in situations when we want to give this to Google, we'd like it to be as small & fast as possible. But we also want it to be ergonomic for us, if we want to generate the WVG fast. WDYT?

[EmilLuta]

All in all looks fine for PoC to provide to google. I would've made a workflow where you can give either the circuits path or the WVG path. If you give circuits, you create WVG from it and pass it to circuit proving. If you give WVG, you just load it and do gpu proving.

Given it's meant to be a one use for GCP, I wouldn't invest more time into it.