fix issue, add transit flow, fix cancellation

apps/edr-freight-api/src/modules/bookings/dto/wagon-cancellation.dto.ts

@@ -183,6 +183,19 @@ export class CancelRemainingWagonsDto {
   @IsUUID('4')
   scheduleId!: string;
 
+  @ApiPropertyOptional({
+    description:
+      'Cancel only THESE never-loaded wagons (wagon_booking_allocation ids from ' +
+      'GET /bookings/:id/wagons). Omit to cancel the whole unloaded remainder. ' +
+      'Already-loaded wagons are rejected — they are riding.',
+    type: [String],
+  })
+  @IsOptional()
+  @IsArray()
+  @ArrayNotEmpty()
+  @IsUUID('4', { each: true })
+  wagonAllocationIds?: string[];
+
   @ApiProperty({ description: 'Why the remaining wagons are not riding' })
   @IsString()
   @IsNotEmpty()