feat(warehouse): Batch 5 — Export Ready To Load queue + Auto Load Ready Items

- GET /warehouse-inventory/ready-to-load-export: EXPORT+PASSED+READY_FOR_LOADING items
  with booking details (customer, container, cargo type, route, inspection status)
- Direction filtering via deriveTradeDirection (route-based, not stored field)
- Frontend ReadyToLoadTab: full table (checkbox, booking ref/id, customer, container,
  cargo type, weight, route, inspection status, current status) with selection
- Auto Load Ready Items button reuses existing POST /load-passed-export endpoint
- Replaces "Ready To Load — coming in the next batch" placeholder in Export sub-tabs

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/edr-freight-web/backoffice/src/constants/URLS.ts

@@ -311,6 +311,7 @@ export const URL_CONSTANTS = {
     RECEIVE_BULK: '/warehouse-inventory/receive-bulk',
     LOAD_PASSED_EXPORT: '/warehouse-inventory/load-passed-export',
     BULK_MARK_INSPECTED: '/warehouse-inventory/bulk-mark-inspected',
+    READY_TO_LOAD_EXPORT: '/warehouse-inventory/ready-to-load-export',
   },
 
   WAREHOUSE_LOADINGS: {