update order as admin

src/modules/orders/dto/update-order-item-quantity.dto.ts

@@ -0,0 +1,16 @@
+import { ApiProperty } from '@nestjs/swagger';
+import { IsNotEmpty, IsNumber, Min } from 'class-validator';
+import { Type } from 'class-transformer';
+
+export class UpdateOrderItemQuantityDto {
+  @ApiProperty({
+    description: 'New quantity for the order item (supports decimals for variable products)',
+    example: 2,
+    minimum: 0.001,
+  })
+  @IsNotEmpty()
+  @Type(() => Number)
+  @IsNumber({ maxDecimalPlaces: 3 })
+  @Min(0.001)
+  quantity!: number;
+}