gpu-warmup pre-provisions an L40S node so hyperopt / train-best don't
pay autoscaler latency at workflow start. When hyperopt-trials=0
(the precompute-only path used by scripts/argo-precompute.sh), both
downstream consumers are skipped via their `when:` clauses and the
warmup-provisioned GPU node would sit idle until workflow end.
Add the same `when:` clause to gpu-warmup so it skips alongside its
consumers, saving an L40S node's provisioning + idle time for every
fxcache-rebuild submission.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
d5896ef809