implement batch board notification system for schedule changes and updates

packages/types/src/freight/booking-window-ws.ts

@@ -32,9 +32,22 @@ export interface BookingWindowPhaseEvent {
   scheduledDepartureDate: string | null;
 }
 
+/**
+ * Payload pushed whenever server-side state behind a schedule's batch board
+ * changes outside a phase transition (payment settled, allocation run, batch
+ * fill, reservation expiry, doc review, …). Carries no board data — clients
+ * refetch the views they hold; `reason` exists for debugging/telemetry only.
+ */
+export interface BatchBoardChangedEvent {
+  scheduleId: string;
+  reason: string;
+  at: string;
+}
+
 /** Socket.io event names pushed server → client on the booking-windows namespace. */
 export const BOOKING_WINDOW_WS_EVENTS = {
   PHASE: "booking-window:phase",
+  BATCH_CHANGED: "batch-board:changed",
 } as const;
 
 /** Socket.io namespace the booking-window gateway listens on. */