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' })