This is designed to satisfy point (1) below.

From sync discussion: there are now two phases to this:

1. document numNodes=0
2. remove numNodes in a future API version

For the 25.8.0 release, we only do (1).

We'll have to think about if for an explicit numNodes=0 we also want to add a new CD-global Status Unknown, which could be phase 1.5 (experimentation: https://github.com/jgehrcke/k8s-dra-driver-gpu/tree/jp/numnodes-optional).

Originally posted by @jgehrcke in #364