Detect multiple GPUs

I have a dual Radeon AI PRO R9700 setup. llmfit does not seem to detect that I have both GPUs and provide appropriate recommendations.

Start by reproducing the dual Radeon AI PRO R9700 setup described in the issue and trace the existing GPU-detection entry point. Done means both GPUs are detected and model recommendations account for the combined hardware; the payload names no files or tests, so those will need to be located first.

Written by the indexing model from the issue text.