feat: add warehouse gate times editor modal for import trucks

Enable per-truck editing of warehouse gate arrival/departure times
(arrivedAt/departedAt) via modal on Import Trucks page. Accessible via
row action menu for EDR-haulage trucks. Includes backend endpoint
POST /last-mile/:id/warehouse-gate-times and frontend modal with
DateTimePicker inputs.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

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

@@ -155,4 +155,13 @@ export const lastMileService = {
       returnedAt?: string | null;
     }>,
   ) => api.post<LastMileRecord>(`${LM.BASE}/${id}/detention-times`, { trucks }),
+  /** Set warehouse gate arrival/departure times for each truck. */
+  setWarehouseGateTimes: (
+    id: string,
+    trucks: Array<{
+      vehicleId: string;
+      arrivedAt?: string | null;
+      departedAt?: string | null;
+    }>,
+  ) => api.post<LastMileRecord>(`${LM.BASE}/${id}/warehouse-gate-times`, { trucks }),
 };