fix: index page layout — separate badge from reconnect, space buttons

- Device card: top row with icon+name+badge, reconnect button below
- Action buttons wrapped in flex column with 20rpx gap
- Removed inline device-battery, now part of device-meta row

miniprogram/pages/index/index.wxml

@@ -18,15 +18,18 @@
 
   <view class="page-content" wx:if="{{!loading && hasDevice}}">
     <view class="device-card">
-      <view class="device-icon">💆</view>
-      <view class="device-name">{{deviceName || '我的光面膜'}}</view>
-      <text class="status-badge status-badge-green" wx:if="{{connected}}">已连接</text>
-      <text class="status-badge" style="background:#ccc;" wx:else>未连接</text>
-      <button class="btn-secondary btn-sm" bindtap="onConnectBle" wx:if="{{hasDevice && !connected}}">重新连接</button>
-      <view class="device-battery" wx:if="{{connected}}">
-        <text>🔋</text>
-        <text>电量 {{battery}}%</text>
+      <view class="device-card-top">
+        <view class="device-icon">💆</view>
+        <view class="device-info">
+          <view class="device-name">{{deviceName || '我的光面膜'}}</view>
+          <view class="device-meta">
+            <text class="status-badge status-badge-green" wx:if="{{connected}}">已连接</text>
+            <text class="status-badge" style="background:#ccc;" wx:else>未连接</text>
+            <text class="device-battery-text" wx:if="{{connected}}">🔋 {{battery}}%</text>
+          </view>
+        </view>
       </view>
+      <button class="btn-reconnect" bindtap="onConnectBle" wx:if="{{hasDevice && !connected}}">重新连接</button>
     </view>
 
     <view class="sub-info" bindtap="onViewSubscription">
@@ -38,7 +41,9 @@
       <text class="sub-info-arrow">›</text>
     </view>
 
-    <button class="btn-primary" bindtap="onStartTreatment">开始护理</button>
-    <button class="btn-secondary" bindtap="onManageDevice">设备管理</button>
+    <view class="action-buttons">
+      <button class="btn-primary" bindtap="onStartTreatment">开始护理</button>
+      <button class="btn-secondary" bindtap="onManageDevice">设备管理</button>
+    </view>
   </view>
 </view>