The guard filter for a SET of instances in one datasource — the single
definition every per-instance read delegates to (instanceGuardQuery).
Reactive adapters subscribe it as ONE shared live query per resource for
every co-mounted session, fanning results back out per sourceInstanceId,
so a document's guard subscription count doesn't grow with its instance
count. Deterministically ordered, matching guardsForResource.
The guard filter for a SET of instances in one datasource — the single definition every per-instance read delegates to (instanceGuardQuery). Reactive adapters subscribe it as ONE shared live query per resource for every co-mounted session, fanning results back out per
sourceInstanceId, so a document's guard subscription count doesn't grow with its instance count. Deterministically ordered, matching guardsForResource.