pub(super) fn handle_report_backend_window_id_registered(
state: &mut State,
label: String,
window_id: String,
) -> Vec<Event>Expand description
Phase B.5 (window_id_map step a) — record the host-reported label → backend_window_id mapping. Idempotent on duplicate label (overwrites with the new ID and emits a fresh event so subscribers see the latest mapping).