feat: 新增退款凭证

openspec/changes/update-payment-voucher-drag-upload/specs/order-management/spec.md

@@ -2,7 +2,7 @@
 
 ### Requirement: Order Voucher Drag Upload
 
-The system SHALL support drag-and-drop image selection for payment vouchers in the admin order creation dialog.
+The system SHALL support drag-and-drop selection of any browser-recognized image format for payment vouchers in the admin order creation dialog.
 
 #### Scenario: Drag image into order voucher upload area
 
@@ -17,4 +17,11 @@ The system SHALL support drag-and-drop image selection for payment vouchers in t
 - **GIVEN** 用户正在后台“订单管理”中创建线下支付订单
 - **WHEN** 用户点击支付凭证上传区选择一张符合要求的图片
 - **THEN** 系统 MUST 继续支持原有点击选择行为
-- **AND** 系统 MUST NOT 因新增拖拽能力破坏原有单文件限制、类型校验和大小校验
+- **AND** 系统 MUST NOT 因新增拖拽能力破坏原有单文件限制和类型校验
+
+#### Scenario: Upload any image format order payment voucher without frontend size limit
+
+- **GIVEN** 用户正在后台“订单管理”中创建线下支付订单
+- **WHEN** 用户选择或拖入任意浏览器识别为图片类型的支付凭证
+- **THEN** 系统 MUST NOT reject the file based on frontend file size checks
+- **AND** 系统 MUST accept the file when its MIME type starts with `image/`