Set of matching item IDs, or null when no cluster/zoom filter is active (all items match).
Matching normalized items (all items when no filter is active).
Human-readable label of the active filter (e.g. 'Oct 15' or '2024'), or null when unfiltered.
ReadonlyActiveReadonlyActiveHuman-readable label of the active filter (e.g. 'Oct 15' or '2024'), or null when unfiltered.
ReadonlyActiveReadonlyFilteredSet of matching item IDs, or null when no cluster/zoom filter is active (all items match).
ReadonlyFilteredMatching normalized items (all items when no filter is active).
Unified filter event emitted whenever cluster selection or era zoom changes the active subset of items.