The poll engine already builds a per-cycle batch; TwinCAT now forwards it as
OnDataChangeBatch, so DriverInstanceActor gets one message per poll cycle
instead of one per changed tag. Because the actor subscribes ONLY the batch
event of a batch-capable driver, every native-path data change (pushes, the
BadNodeIdUnknown / refusal / unavailable snapshots) is raised through a single
RaiseDataChange that fires both the per-tag event and a fresh one-item batch.
Refs #739
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT