feat: harden phase one workflows

miniapp/miniprogram/pages/group-buy/index.wxml

@@ -1,14 +1,29 @@
 <view class="page">
-  <view class="section-title">今日团购</view>
-  <view wx:for="{{groupBuys}}" wx:key="id" class="card" bindtap="goDetail" data-id="{{item.id}}">
-    <view class="row between">
-      <view>
-        <view>{{item.title}}</view>
-        <view class="muted">截单 {{item.endTime}}</view>
-      </view>
-      <view class="price">¥{{item.priceCent / 100}}</view>
-    </view>
-    <view class="muted">库存 {{item.stock}} / 已售 {{item.soldCount}}</view>
+  <view class="page-heading">
+    <view class="heading-eyebrow">社区拼单</view>
+    <view class="heading-title">今日团购</view>
+    <view class="heading-subtitle">集中采购，邻里共享实惠</view>
   </view>
-  <view wx:if="{{!groupBuys.length && !loading}}" class="card muted">暂无团购</view>
+
+  <view class="group-list">
+    <view wx:for="{{groupBuys}}" wx:key="id" class="group-card" bindtap="goDetail" data-id="{{item.id}}">
+      <image wx:if="{{item.coverUrl}}" class="group-cover" src="{{item.coverUrl}}" mode="aspectFill" />
+      <view wx:else class="group-cover media-placeholder">团</view>
+      <view class="group-body">
+        <view class="row between">
+          <view class="card-title">{{item.title}}</view>
+          <view class="price">¥{{item.priceCent / 100}}</view>
+        </view>
+        <view class="muted">截单 {{item.endTime}}</view>
+        <view class="stock-line">
+          <view class="stock-track">
+            <view class="stock-fill"></view>
+          </view>
+          <view class="muted">库存 {{item.stock}} / 已售 {{item.soldCount}}</view>
+        </view>
+      </view>
+    </view>
+  </view>
+
+  <view wx:if="{{!groupBuys.length && !loading}}" class="empty-state">暂无团购</view>
 </view>