feat: production readiness — feature gaps + config hardening

Miniprogram:
- Add BLE reconnect button on home page when disconnected
- Add loading states to index, profile, subscribe-plans pages
- Add profile editing (avatar + nickname) with COS upload
- Enable pull-to-refresh on history page
- Fix auto-scan self.options → self.data inconsistency
- Add console.error to silent catch blocks
- Gate 'Simple Peripheral' BLE scan behind __DEV__ flag
- Add production config comment to env.js

Admin console:
- Add empty state '暂无数据' to all 5 list views
- Replace plain text plan input with select dropdown
- Add type="date" to record date filters
- Add production config comment

Server:
- CORS origin restricted in production (env CORS_ORIGIN)
- DB pool size configurable via DB_POOL_SIZE env var
- .env.example updated with WeChat Pay + production fields

miniprogram/pages/index/index.js

@@ -14,7 +14,8 @@ Page({
     bleState: 'disconnected',
     hasDevice: false,
     deviceInfo: null,
-    devMode: false
+    devMode: false,
+    loading: true
   },
 
   onShow: function () {
@@ -47,9 +48,9 @@ Page({
       return
     }
 
-    self.setData({ connected: ble.isConnected() })
+    self.setData({ connected: ble.isConnected(), loading: true })
 
-    api.getDevices().then(function (data) {
+    var p1 = api.getDevices().then(function (data) {
       var devices = data.devices || []
       self.setData({ hasDevice: devices.length > 0 })
       if (devices.length > 0) {
@@ -59,14 +60,22 @@ Page({
           deviceInfo: devices[0]
         })
       }
-    }).catch(function () {})
+    }).catch(function (err) {
+      console.error('getDevices failed', err)
+    })
 
-    api.getSubscription().then(function (sub) {
+    var p2 = api.getSubscription().then(function (sub) {
       self.setData({
         subscription: sub,
         subRemaining: sub.remaining_days || 0
       })
-    }).catch(function () {})
+    }).catch(function (err) {
+      console.error('getSubscription failed', err)
+    })
+
+    Promise.all([p1, p2]).then(function () {
+      self.setData({ loading: false })
+    })
   },
 
   onBleStatus: function (status) {
@@ -88,7 +97,9 @@ Page({
       },
       onConnected: function () {
         self.setData({ connected: true, bleState: 'connected' })
-        ble.queryStatus().catch(function () {})
+        ble.queryStatus().catch(function (err) {
+          console.error('queryStatus failed', err)
+        })
       },
       onError: function (err) {
         self.setData({ connected: false, bleState: 'error' })

miniprogram/pages/index/index.wxml

@@ -1,5 +1,10 @@
 <view class="page">
-  <view class="page-content" wx:if="{{!hasDevice}}">
+  <view class="loading-container" wx:if="{{loading}}">
+    <view class="loading-spinner"></view>
+    <text class="loading-text">加载中...</text>
+  </view>
+
+  <view class="page-content" wx:if="{{!loading && !hasDevice}}">
     <view class="empty-device">
       <text class="empty-icon">📱</text>
       <view class="empty-text">还没有绑定设备</view>
@@ -11,12 +16,13 @@
     </view>
   </view>
 
-  <view class="page-content" wx:if="{{hasDevice}}">
+  <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>

miniprogram/pages/index/index.wxss

@@ -42,3 +42,30 @@
   color: #999;
   font-size: 32rpx;
 }
+
+.loading-container {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  padding: 200rpx 0;
+}
+
+.loading-spinner {
+  width: 64rpx;
+  height: 64rpx;
+  border: 6rpx solid #f0f0f0;
+  border-top-color: #E6508C;
+  border-radius: 50%;
+  animation: spin 0.8s linear infinite;
+}
+
+@keyframes spin {
+  to { transform: rotate(360deg); }
+}
+
+.loading-text {
+  margin-top: 20rpx;
+  font-size: 28rpx;
+  color: #999;
+}