Align singleuser resource configuration keys with k8s defaults for 5.x release

[samyuh]

Problem

Currently, resource limits and guarantees for single-user pods are configured using custom keys in the Helm chart:

singleuser.cpu:
  limit: ...
  guarantee: ...

singleuser.memory:
  limit: ...
  guarantee: ...

While functional, this deviates from the standard Kubernetes resource configuration schema. To improve clarity and align with Kubernetes best practices, I propose we adopt the native resource format:

resources:
  requests:
    cpu: ...
    memory: ..
  limits:
    cpu: ...
    memory: ...

Rationale

• Follows Kubernetes conventions, making it more intuitive for users.
• Improves transparency and predictability of resource allocation.

It’s unclear if the current custom structure was introduced for a specific reason. If so, feel free to close this issue. If not, we should consider deprecating the current structure and transitioning to the standard format.

This would be a breaking change, so we should only introduce it in the 5.x release.