fix train build

apps/edr-freight-web/backoffice/src/services/wagon.service.ts

@@ -28,6 +28,10 @@ export interface Wagon {
   status: Freight.WagonStatus;
   currentYardId: string | null;
   currentYard?: { id: string; label?: string; code?: string } | null;
+  /** Odd EXPORT run (Ethiopia → Djibouti); null when the wagon is not on a run. */
+  exportTrainNumber?: string | null;
+  /** Even IMPORT run (Djibouti → Ethiopia); always the export run + 1. */
+  importTrainNumber?: string | null;
   notes?: string;
 }