feat(r3-order-pay): 结算与订单支付流程、支付倒计时/商品图组件，接口地址改为构建期注入

- 新增 PaymentCountdown、ProductImage 组件
- 完善 checkout/orders/orderDetail 订单支付链路与地址、商品、设计数据
- request 接口地址改为构建期注入并保留真实网络错误，默认兜底线上地址
- 同步重新构建 dist 产物

src/pages/shop/detail/index.tsx

@@ -1,8 +1,9 @@
-import { View, Text, Image, ScrollView } from '@tarojs/components'
+import { View, Text, ScrollView } from '@tarojs/components'
 import Taro from '@tarojs/taro'
 import { useState, useEffect, useCallback, useMemo } from 'react'
 import './index.scss'
 import { PRODUCTS } from '../../../utils/productConfig'
+import { fetchProduct } from '../../../utils/api/product'
 import { ProductCategory } from '../../../types'
 import { useSafeArea } from '../../../hooks/useSafeArea'
 import { useStatusBar } from '../../../hooks/useStatusBar'
@@ -10,6 +11,7 @@ import { useThemeContext } from '../../../context/ThemeContext'
 import ThemedPageMeta from '../../../components/ThemedPageMeta'
 import ScrollTopMask from '../../../components/ScrollTopMask'
 import BottomActionBar from '../../../components/BottomActionBar'
+import ProductImage from '../../../components/ProductImage'
 
 const clamp = (v: number, min: number, max: number) => Math.min(Math.max(v, min), max)
 const lerp = (a: number, b: number, t: number) => a + (b - a) * t
@@ -26,7 +28,12 @@ export default function ShopDetailPage() {
   const routerParams = Taro.getCurrentInstance().router
   const routerParamsValues = routerParams ? routerParams.params : undefined
   const productId = routerParamsValues ? routerParamsValues.id : ''
-  const product: ProductCategory | undefined = PRODUCTS.find(p => p.id === productId)
+  const [product, setProduct] = useState<ProductCategory | undefined>(PRODUCTS.find(p => p.id === productId))
+
+  useEffect(() => {
+    if (!productId) return
+    fetchProduct(productId).then(setProduct).catch(() => { /* 保留本地兜底 */ })
+  }, [productId])
 
   useEffect(() => {
     try {
@@ -132,9 +139,10 @@ export default function ShopDetailPage() {
             transform: `translateY(${winHeight * heroStyles.translateY / 100}px)`
           }}
         >
-          <Image
+          <ProductImage
             className="shop-hero-img"
             src={(product.images && product.images[0]) || product.iconImg || ''}
+            fallback={product.iconImg || product.icon}
             mode="aspectFill"
             style={{
               width: '100%',