refactor: 常量化订单状态 + 支付渠道/提供商分离显示 + H5自动跳转

- 新增 src/lib/constants.ts，集中管理 ORDER_STATUS / PAYMENT_TYPE / PAYMENT_PREFIX 等常量
- 后端 service/status/timeout/limits 全量替换魔法字符串为 ORDER_STATUS.*
- PaymentTypeMeta 新增 provider 字段，分离 sublabel（选择器展示）与 provider（提供商名称）
- getPaymentDisplayInfo() 返回 { channel, provider } 用于用户端/管理端展示
- 支持通过 PAYMENT_SUBLABEL_* 环境变量覆盖默认 sublabel
- PaymentQRCode: H5 支付自动跳转（含易支付微信 weixin:// scheme 兜底）
- 订单列表/详情页：显示可读的渠道名+提供商，不再暴露内部标识符

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/components/admin/OrderDetail.tsx

@@ -1,6 +1,6 @@
 'use client';
 
-import { getPaymentTypeLabel } from '@/lib/pay-utils';
+import { getPaymentDisplayInfo } from '@/lib/pay-utils';
 
 interface AuditLog {
   id: string;
@@ -55,7 +55,8 @@ export default function OrderDetail({ order, onClose, dark }: OrderDetailProps)
     { label: 'Payment OK', value: order.paymentSuccess ? 'yes' : 'no' },
     { label: 'Recharge OK', value: order.rechargeSuccess ? 'yes' : 'no' },
     { label: 'Recharge Status', value: order.rechargeStatus || '-' },
-    { label: '支付方式', value: getPaymentTypeLabel(order.paymentType) },
+    { label: '支付渠道', value: getPaymentDisplayInfo(order.paymentType).channel },
+    { label: '提供商', value: getPaymentDisplayInfo(order.paymentType).provider || '-' },
     { label: '充值码', value: order.rechargeCode },
     { label: '支付单号', value: order.paymentTradeNo || '-' },
     { label: '客户端IP', value: order.clientIp || '-' },

src/components/admin/OrderTable.tsx

@@ -1,6 +1,6 @@
 'use client';
 
-import { getPaymentTypeLabel } from '@/lib/pay-utils';
+import { getPaymentDisplayInfo } from '@/lib/pay-utils';
 
 interface Order {
   id: string;
@@ -94,7 +94,21 @@ export default function OrderTable({ orders, onRetry, onCancel, onViewDetail, da
                     {statusInfo.label}
                   </span>
                 </td>
-                <td className={tdMuted}>{getPaymentTypeLabel(order.paymentType)}</td>
+                <td className={tdMuted}>
+                  {(() => {
+                    const { channel, provider } = getPaymentDisplayInfo(order.paymentType);
+                    return (
+                      <>
+                        {channel}
+                        {provider && (
+                          <span className={dark ? 'ml-1 text-xs text-slate-500' : 'ml-1 text-xs text-slate-400'}>
+                            {provider}
+                          </span>
+                        )}
+                      </>
+                    );
+                  })()}
+                </td>
                 <td className={tdMuted}>{order.srcHost || '-'}</td>
                 <td className={tdMuted}>{new Date(order.createdAt).toLocaleString('zh-CN')}</td>
                 <td className="whitespace-nowrap px-4 py-3 text-sm">