add company stamp upload functionality for contract signing

- Introduced StampUpload component for uploading company stamp images.
- Integrated stamp upload in contract signing modal, supporting PNG and JPG formats.
- Implemented validation for file type and size (max 5 MB).
- Added visual feedback for drag-and-drop functionality.
- Updated contract-related pages to handle duplicate contract alerts and pricing notices.
- Enhanced contract expiry management with a nightly sweep service.
- Added unit tests for new features and updated existing tests for contract handling.

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

@@ -12,6 +12,7 @@ import type {
   BookingLoadResult,
   BookingUnloadResult,
   CompositionRemovalEntry,
+  DocReviewAlert,
   UnassignedBookingsResponse,
   CreateTrainSchedulePayload,
   EligibleContainerBookingsResponse,
@@ -709,6 +710,15 @@ export const trainSchedulingService = {
     return unwrap(response.data);
   },
 
+  getDocReviewAlert: async (): Promise<DocReviewAlert | null> => {
+    const response = await client.get<DocReviewAlert | null>(
+      URL_CONSTANTS.TRAIN_SCHEDULING.DOC_REVIEW_ALERT,
+    );
+    // "No alert" comes back as null — which Nest sends as an empty body, so
+    // coerce anything falsy to null (react-query rejects undefined).
+    return unwrap(response.data) || null;
+  },
+
   updateGlobalRules: async (
     payload: Partial<Omit<TrainSchedulingGlobalRules, "id">>,
   ): Promise<TrainSchedulingGlobalRules> => {