[RFE] Skip endpoint creation for same-cluster StorageClass PVC conversion

[stillalearner]

Summary

Improve crane transfer-pvc for same-cluster StorageClass conversion so it does not require or create a public
endpoint (--endpoint) when source and destination PVCs are in the same cluster.

Motivation

For same-cluster PVC conversion, Crane when currently uses the direct-transfer path and requires an endpoint such
as an OpenShift Route or Kubernetes Ingress. The rsync source and destination Pods already run in the same
cluster, so exposing a temporary public endpoint is unnecessary and may be disallowed by cluster networking
policy.

Proposed behavior

When source and destination contexts resolve to the same cluster:

• Detect same-cluster transfer automatically.
• Create rsync client/server Pods that communicate through an internal ClusterIP Service.
• Do not require --endpoint, --ingress-class, or --subdomain.
• Avoid creating Routes or Ingress resources.
• Retain the existing same-cluster/different-PVC-name validation.
• Continue supporting --dest-storage-class for conversion workflows.

Acceptance criteria

• Same-cluster transfers complete without --endpoint.
• No Route or Ingress is created for same-cluster transfers.
• Source and destination PVCs can have different names and StorageClasses in the same namespace.
• Internal service communication is used for the rsync transfer.
• Cross-cluster transfers retain existing endpoint behavior.
• Tests cover same-cluster conversion and ensure no endpoint resources are created.