container toolkit

The four layers between `nvidia.com/gpu: 4` and a container that can run CUDA, the one failure each layer produces, the stranded-GPU arithmetic the integer model causes, and why Dynamic Resource Allocation replaces the count with a claim.

A node with eight healthy H100s that Kubernetes thinks has none. The layered check from kernel driver to container toolkit to device plugin to taints and allocatable, in the order that isolates the fault fastest, with the log lines each layer prints when it is the one that broke.