fix: correct Slurm and k8s labels, hybrid diagram

[ruhomor]

This PR fixes an error in the architecture-slurm-hybrid.svg diagram where the roles of Slurm Cluster and Kubernetes were mistakenly swapped.

The correction improves the clarity of the hybrid architecture documentation and prevents confusion for users interpreting the infrastructure layout.

[lexbuchi]

Absolutely agree. The correction is important for maintaining clarity and preventing misinterpretation of the hybrid infrastructure.

[ruhomor]

Please accept this — the client at my workplace genuinely believes that placing Kubernetes inside Slurm is a good architectural decision.

[SkylerMalinowski]

The diagram's labels are correct. Each outer box represents a conceptual domain. In hybrid, the Slurm cluster will cross at least two domains. In this case, Kubernetes and Bare-metal/VM are the diagrammed domains.

slurm-operator pre-supposes Kubernetes, hence why the diagram primarily has a Kubernetes centric Slurm cluster. Support for more flexible hybrid configurations will be added with later, and more diagrams to illustrate some of these cluster configurations.

Please accept this — the client at my workplace genuinely believes that placing Kubernetes inside Slurm is a good architectural decision.

It is an organizational decision as to how they wish to reconcile Kubernetes and Slurm clusters. Slinky offers multiple methodologies that can work in concert together. slurm-operator aims to allow one or more Slurm cluster components to reside in Kubernetes. slurm-bridge allows Slurm to schedule Kubernetes workload (in addition to its own).