Restore picks up backups that aren't actually in the cluster

Restore picks up backups that aren't actually in the cluster: a task in MiMo-V2.6-RL-oss: Agentic RL Environments (MiMo RL release). I'm running Ark with a couple of BackupStorageLocations configured (one default + one extra). I ran into some behavior around restores that I think is a bug, or at…