Optional ReadonlysoundcardThe device.ids present now (issue #833) — the stable identity a nick-derived label
(an HDMI sink's EDID-sourced name) cannot guarantee across a save/restore gap. When
given, the diff prefers this over a soundcards label match; absent for a legacy
caller, which falls back to soundcards alone.
ReadonlysoundcardsThe soundcard band labels present now.
Optional ReadonlystageboxesThe detected reac-pw stageboxes with their live reac.link-state / box identity, so the
diff can tell a locked box apart from a bridge still probing an empty wire (issue #201).
When present it is authoritative for stagebox presence; when omitted the diff falls back
to stageboxIds (legacy callers). A detected-but-not-established box is flagged
"not connected"; an expected box with no detected node at all is "REAC bridge down".
ReadonlystageboxThe detected stagebox device ids present now. A detected id is the reac-pw BRIDGE, not proof of a box; when stageboxes is given the diff uses the live link state instead (issue #201). Retained for callers that already pre-filtered to connected boxes.
ReadonlysurfaceThe control-surface adapter ids present now.
What is actually present on the rig now, for the restore-time diff.