PR #939 added the awaiting_plate_clear gate but stored it on
PrinterManager, not on PrinterState. printer_state_to_dict() — which
builds every WebSocket printer_status payload — never emitted the flag,
so the frontend's WS merge preserved the stale false value. The only
path that surfaced true was the 30s HTTP fallback poll, and incoming WS
ticks kept bumping React Query's dataUpdatedAt, pushing the refetch out
further on chatty printers.
Emit awaiting_plate_clear from printer_state_to_dict by reading
printer_manager.is_awaiting_plate_clear(printer_id) directly; returns
False when no id is passed. No frontend change needed — the existing WS
merge carries the flag end-to-end and the button now appears the instant
the printer transitions to FINISH.
Regression tests assert the WS dict always contains the key and surfaces
True when the manager has the flag set for that printer_id.
Affects every printer (A1/H2D/X1C) equally — transport-agnostic path.
maziggy
4e86e8cb16