add items per wagon map to cargo types and sync bulk rate units

- Implemented  in the  to manage the physical item capacity for each wagon type.
- Added a new migration to create the  column in the  table.
- Introduced  method in  to update rate units when cargo type unit of measure changes.
- Updated booking calculations to consider items per wagon for break-bulk cargo.
- Refactored various components to utilize the new items fit logic and ensure consistent date formatting across the application.
- Added tests for the new display timezone functionality to ensure consistent date/time representation across different user settings.

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

@@ -69,6 +69,7 @@ import {
   LocomotiveLimits,
   WagonTypeDimensions,
   bookingCargoTons,
+  bulkItemsFitFor,
   bulkItemWagonsRequired,
   bookingGrossWeightTons,
   deriveTrainCapacityFromLocomotive,
@@ -4060,7 +4061,13 @@ export class BookingBatchService implements OnModuleInit {
 
     // Break-bulk (PER_ITEM): indivisible items can need more wagons than raw
     // tonnage suggests (floor items-per-wagon loses the fractional capacity).
-    const byItems = bulkItemWagonsRequired(booking, capacityTons);
+    // `dimsFor` resolved dims from the first allowed wagon type, so charge that
+    // same type's configured items-fit alongside its capacity.
+    const byItems = bulkItemWagonsRequired(
+      booking,
+      capacityTons,
+      bulkItemsFitFor(booking.cargoType, booking.cargoType?.wagonTypes?.[0]?.id),
+    );
 
     return Math.max(DEFAULT_WAGONS_PER_BOOKING, stored, byLength, byWeight, byItems);
   }