rsc_update
Resource update helper module used by m_rsc.
This module contains insert/update/delete/merge routines for resources and is logically part of the m_rsc model implementation.
It is not exposed as a standalone model path endpoint.
Resource insert/update MQTT events include version, previous_version and
reason. Background media workers can pass the update option
{update_reason, media_processing}. The reason is media_processing
only if that resource's properties are unchanged apart from version, modified
and modifier_id; otherwise it is update. Clients must still check consecutive
versions before acknowledging processing updates on an unsaved form.