mod_cloud_notify: use stanza from mod_smacks to behave O(1) This uses the provided stanza in the ack-delayed smacks event to trigger push for this stanza only rather than iterating through the whole smacks queue to find the first unpushed stanza.

This module discards typing notifications sent to a bare host JID,
preventing error replies to be sent. These errors are harmless but can
be annoying sometimes if your client shows them prominently.