fix(app): 优化首页会员卡闪烁和即将上课卡片交互

- CardShop: 采用 stale-while-revalidate 模式，仅首次加载显示骨架屏，
  切换 tab 回来时保留旧数据静默刷新，消除列表闪烁
- UpcomingBooking: 补充 PENDING_CONFIRMATION 状态的中文映射和样式
- UpcomingBooking: 卡片点击跳转到预约详情页

packages/app/src/components/CardShop.vue

@@ -79,16 +79,25 @@ import { formatPrice, getCardCoverClass } from '../utils/format'
 
 const cardTypes = ref<CardType[]>([])
 const loading = ref(false)
+const hasLoaded = ref(false)
 
 async function fetchCardTypes() {
-  loading.value = true
+  // Stale-While-Revalidate: only show skeleton on first load
+  // Subsequent refreshes silently update data in background
+  if (!hasLoaded.value) {
+    loading.value = true
+  }
   try {
     const result = await get<CardType[]>('/membership/card-types')
     cardTypes.value = result
       .filter((c) => c.isActive)
       .sort((a, b) => a.sortOrder - b.sortOrder)
+    hasLoaded.value = true
   } catch {
-    uni.showToast({ title: '加载会员卡失败', icon: 'none' })
+    // Only show error toast on first load; silent fail on background refresh
+    if (!hasLoaded.value) {
+      uni.showToast({ title: '加载会员卡失败', icon: 'none' })
+    }
   } finally {
     loading.value = false
   }