fix issue, add transit flow, fix cancellation

apps/edr-freight-api/src/modules/train-scheduling/services/train-scheduling.service.ts

@@ -2320,12 +2320,18 @@ export class TrainSchedulingService {
       // batch fill, which unlinks it and frees its wagons on the next window cycle.
       const scheduledAt = new Date();
       for (const booking of bookings) {
+        const wagonsRequired = sumWagonsRequired(booking, wagonPlan);
         await this.bookingsRepository.updateSchedulingFields(
           booking.id,
           {
             schedulingStatus: SchedulingStatus.Scheduled,
             scheduledAt,
-            wagonsRequired: sumWagonsRequired(booking, wagonPlan),
+            wagonsRequired,
+            // Pinned for cancellation pricing: unassign clears wagonsRequired,
+            // this stays. Written once — re-allocation keeps the first stamp.
+            ...(Number(booking.cancellationWagons ?? 0) > 0
+              ? {}
+              : { cancellationWagons: wagonsRequired }),
           },
           manager,
         );