OptionalbackendOptionalcodeReads the daemon's own code on disk again; called on each attach, so a
surface arriving after an upgrade learns at once. The host answers
through stale_set. Omitted, the daemon never calls itself stale.
OptionalelevationThe door a surface can be raised at with the person's password (elevate); absent, a session stays as it was started.
OptionalhostOptionalhostThe host-control tiers this daemon declares (empty or absent when off).
OptionalportOptionalpromptOptionalscrollbackOptionalstackThe hosting process's versions and build hash, reported on attach.
OptionaltelemetrySupplies the live process-index counts for the once-a-second telemetry heartbeat. Omitted, no heartbeat is sent (e.g. tests).
Optionalweb
The session's backend id, reported on attach so a surface draws its composition.