Async suspend (pause) should not detach the actor's volumes #2734

SuspendActor runs ensureVolumesDetached (DetachVolumes) for both modes in cmd/ateapi/internal/controlapi/workflow_suspend.go. An async suspend (pause) keeps its snapshot on the node and AssignedNode stays set, so the actor can resume on the same node. Detaching its volumes there forces a resume on that node to reattach them for nothing.

Expected

Only a sync (durable) suspend should detach volumes. An async suspend should leave them attached; they get detached when the actor is later suspended durably, deleted, or resumed on a different node.

Context

Behavior inherited from the pause workflow and kept as-is in the refactor that merged pause into suspend (#2694), marked with a TODO at the call site.