Add slinky.slurm.net/v1beta1 NodeSet Karta sample

[lavianalon]

Add a Karta workload definition for SchedMD Slinky NodeSet (slurm-operator) under docs/samples/nodeset.yaml.

Why

NodeSet manages Slurm compute nodes (slurmd pods) on Kubernetes — the core scalable unit of Slinky. A Karta definition surfaces it to schedulers, dashboards, and autoscalers as a standard pod-set workload.

Details (verified against SlinkyProject/slurm-operator source)

• apiVersion / kind: slinky.slurm.net/v1beta1 / NodeSet (v1beta1, not v1alpha1)
• Manages a homogeneous set of slurmd pods. StatefulSet-like by default (stable identity, ordinals, PVC templates). spec.scalingMode = StatefulSet (default) | DaemonSet.
• Pod template: spec.template (a custom PodTemplate type; pod spec at spec.template.spec, labels at spec.template.metadata.labels — same shape as a podTemplateSpec for podTemplateSpecPath purposes)
• Replicas: spec.replicas (ignored in DaemonSet mode). No min/max fields — autoscaled via the HPA scale subresource (.spec.replicas / .status.replicas / .status.selector).
• Status: status.replicas, readyReplicas, availableReplicas, updatedReplicas, desired; Slurm-specific status.slurmIdle / slurmAllocated / slurmDown / slurmDrain; status.conditions[]
• Ownership: NodeSet directly owns its pods (flat StatefulSet-like set, ordinal naming <nodeset>-<ordinal>); no intermediate StatefulSet object.
• Pod selector labels: app.kubernetes.io/name=slurmd, app.kubernetes.io/instance=<nodeset name>, app.kubernetes.io/component=worker, slinky.slurm.net/cluster=<controller name>

Suggested mapping

rootComponent = NodeSet; one childComponent (Pod) with podTemplateSpecPath: .spec.template, replicasPath: .spec.replicas, scale-subresource paths for autoscaling; podSelector by app.kubernetes.io/instance. Status phase from conditions / readyReplicas vs replicas. Optional: surface Slurm node states (slurmIdle/Allocated/Down/Drain) if the status mapping can carry them.

References

• docs/samples/raycluster.yaml (childComponent / scale shape)
• NodeSet type: https://github.com/SlinkyProject/slurm-operator/blob/main/api/v1beta1/nodeset_types.go