changes export flow

apps/edr-freight-api/src/modules/bookings/dto/request-changes.dto.ts

@@ -5,6 +5,7 @@ import {
   IsInt,
   IsOptional,
   IsString,
+  IsUUID,
   Max,
   Min,
   MinLength,
@@ -93,6 +94,17 @@ export class RequestOperationDto {
   })
   @IsDateString()
   scheduledDate!: string;
+
+  @ApiPropertyOptional({
+    description:
+      'EXPORT rail only: the specific train (schedule id) the customer picked ' +
+      'from GET /bookings/:id/export-trains. The reserve path locks onto this ' +
+      'train instead of earliest-first; 409 if it no longer fits. Ignored for ' +
+      'import/domestic/road bookings.',
+  })
+  @IsOptional()
+  @IsUUID()
+  trainScheduleId?: string;
 }
 
 export class OperationReviewDto {