export flow and fix intercity issue

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

@@ -217,10 +217,20 @@ export class IntercityService {
       // board a train that is full only on other legs.
       const leg = budget.legForYards(booking.originYardId, booking.destinationYardId);
       if (!budget.fits(need, leg)) {
+        // Offer the part that DOES fit the leg (split-on-payment): customer is
+        // notified with a pay window for the fitting wagons; the remainder can
+        // be re-booked on a later train. Budget is consumed by the offer so the
+        // next booking in this pass sees the reduced room.
+        const offered = await this.bookingBatchService.offerIntercityPartial(
+          booking,
+          scheduleId,
+          budget,
+        );
         rejected.push({
           bookingId,
-          reason:
-            'Does not fit the remaining wagon/weight/length capacity for this train',
+          reason: offered
+            ? 'Does not fit whole — a partial offer for the wagons that fit was sent to the customer'
+            : 'Does not fit the remaining wagon/weight/length capacity for this train',
         });
         continue;
       }