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-api/src/modules/rule-engine/entities/rate-unit.util.ts

@@ -1,5 +1,17 @@
 import type { RateAppliesTo, RateTrigger, RateUnit } from './rate.entity';
 
+/** How the bulk commodity a rate is scoped to is counted (cargo_types.unit_of_measure). */
+export type CargoUom = 'PER_TON' | 'PER_ITEM' | null | undefined;
+
+/**
+ * Units billed against a booking's bulk quantity. That quantity is recorded in
+ * the commodity's own unit — tonnes for a PER_TON commodity, item count for a
+ * PER_ITEM one — so both units scale off the same field and only differ in what
+ * they are called.
+ */
+export const isBulkQuantityUnit = (unit: string): boolean =>
+  unit === 'PER_TON' || unit === 'PER_ITEM';
+
 /**
  * Which rate units make sense for a given rate shape. The weighting basis is
  * driven by the *type* of thing being billed — a container leg bills per
@@ -8,6 +20,10 @@ import type { RateAppliesTo, RateTrigger, RateUnit } from './rate.entity';
  * ton. This keeps the rate table dynamic yet non-conflicting: the admin can
  * only pick a unit the pricing engine knows how to apply.
  *
+ * A rate scoped to a break-bulk commodity (unit_of_measure = PER_ITEM) offers
+ * PER_ITEM wherever a weighed commodity offers PER_TON — machinery is priced
+ * per unit shipped, wheat per tonne. Per-wagon is offered either way.
+ *
  * Returned lists are ordered with the most natural/default unit first.
  */
 export function allowedRateUnits(input: {
@@ -15,6 +31,19 @@ export function allowedRateUnits(input: {
   trigger: RateTrigger;
   /** CUSTOMS_CLEARANCE only: which cargo kind the fee covers. */
   cargoKind?: 'CONTAINER' | 'BULK' | null;
+  /** Unit of measure of the bulk commodity the rate is scoped to, when any. */
+  cargoUnitOfMeasure?: CargoUom;
+}): RateUnit[] {
+  const units = unitsForShape(input);
+  return input.cargoUnitOfMeasure === 'PER_ITEM'
+    ? units.map((u) => (u === 'PER_TON' ? 'PER_ITEM' : u))
+    : units;
+}
+
+function unitsForShape(input: {
+  appliesTo: RateAppliesTo;
+  trigger: RateTrigger;
+  cargoKind?: 'CONTAINER' | 'BULK' | null;
 }): RateUnit[] {
   const { appliesTo, trigger } = input;
 
@@ -81,6 +110,7 @@ export function isRateUnitAllowed(input: {
   appliesTo: RateAppliesTo;
   trigger: RateTrigger;
   cargoKind?: 'CONTAINER' | 'BULK' | null;
+  cargoUnitOfMeasure?: CargoUom;
   unit: RateUnit;
 }): boolean {
   return allowedRateUnits(input).includes(input.unit);