Add HIP backend

[amd-asalykov]

How to install:

uv add torch --index pytorch=https://download.pytorch.org/whl/rocm7.1

Run on MI350X/MI355X:

uv run python scripts/generate_and_eval_single_sample.py gpu_arch=gfx950 backend=hip dataset_src=huggingface level=1 problem_id=22 server_type=google model_name=gemini/gemini-2.5-flash

Run on MI300X/MI325X:

uv run python scripts/generate_and_eval_single_sample.py gpu_arch=gfx942 backend=hip dataset_src=huggingface level=1 problem_id=22 server_type=google model_name=gemini/gemini-2.5-flash