Currently, there is no reliable single source of truth to determine the backend storage PVC when a VM is using backend storage.

KubeVirt’s internal logic relies on different approaches, such as filtering by label volumes.go#L111 or checking the VMI status backend-storage.go#L124.

If instance types are involved, checking the VM spec alone may not even reveal whether it uses backend storage or not.

The goal of this story is to establish a single source of truth that reliably indicates whether a VM is using backend storage and provides the PVC name, accessible from both the VM and VMI.