DependencyMuxActor now receives DriverInstanceActor.AttributeValueBatchPublished — the
primary value ingress since DriverHostActor's batched fan-out — and filters it per item,
emitting one DependencyValueChanged per genuinely interested (item, subscriber) pair with
that item's own value/timestamp/status sub-code (#519).
The per-item AttributeValuePublished receive stays: DriverHostActor's comms-loss fan
fabricates it, and per-tag drivers still take that path. Indexed for-loop over Items to
avoid an interface-enumerator allocation per burst.
Joseph Doherty
d7edc709cf