新增小程序后端代码，包括数据库、路由、服务层等。

小程序前后端打通，包括登录、注册、绑定设备、查询绑定信息，修改小朋友名称等功能。

banban-mini/src/pages/device/index.tsx

@@ -1,6 +1,7 @@
 import { View, Text, Switch, Slider, Image } from '@tarojs/components'
 import { useState, useEffect } from 'react'
 import Taro from '@tarojs/taro'
+import { getCurrentBinding } from '@/services/binding'
 import './index.scss'
 
 interface DeviceData {
@@ -20,35 +21,59 @@ export default function Device() {
   const [hasDevice, setHasDevice] = useState(false)
 
   useEffect(() => {
-    // 检查登录状态
-    const isLoggedIn = Taro.getStorageSync('isLoggedIn')
-    if (!isLoggedIn) {
+    console.log('[Device] Checking login status...')
+    const token = Taro.getStorageSync('token')
+    console.log('[Device] Token exists:', !!token)
+    
+    if (!token) {
+      console.log('[Device] No token, redirecting to login')
       Taro.redirectTo({ url: '/pages/login/index' })
       return
     }
 
-    // 检查设备绑定状态
-    const deviceInfo = Taro.getStorageSync('deviceInfo')
-    const hasDeviceFlag = Taro.getStorageSync('hasDevice')
-    
-    setHasDevice(!!hasDeviceFlag)
-    
-    if (deviceInfo && hasDeviceFlag) {
-      setDevice({
-        id: deviceInfo.id,
-        name: deviceInfo.name || '小夏的伴伴',
-        status: deviceInfo.status || 'online',
-        battery: deviceInfo.battery || 82,
-        daysLeft: 4,
-        sleepEnabled: true,
-        sleepTime: '每天 22:00 - 07:00',
-        volume: 50
-      })
-    }
-    
-    setIsLoading(false)
+    loadDeviceInfo()
   }, [])
 
+  const loadDeviceInfo = async () => {
+    try {
+      const binding = await getCurrentBinding()
+      console.log('[Device] Got binding:', binding)
+      
+      if (binding) {
+        setHasDevice(true)
+        Taro.setStorageSync('hasDevice', '1')
+        Taro.setStorageSync('deviceInfo', {
+          id: binding.device_id,
+          name: '伴伴设备',
+          status: 'online',
+          battery: 82
+        })
+        setDevice({
+          id: binding.device_id,
+          name: '伴伴设备',
+          status: 'online',
+          battery: 82,
+          daysLeft: 4,
+          sleepEnabled: true,
+          sleepTime: '每天 22:00 - 07:00',
+          volume: 50
+        })
+      } else {
+        setHasDevice(false)
+        Taro.removeStorageSync('hasDevice')
+        Taro.removeStorageSync('deviceInfo')
+      }
+    } catch (err: any) {
+      console.log('[Device] No binding or error:', err?.message || err)
+      if (err?.status === 404) {
+        setHasDevice(false)
+        Taro.removeStorageSync('hasDevice')
+        Taro.removeStorageSync('deviceInfo')
+      }
+    }
+    setIsLoading(false)
+  }
+
   const handleSleepToggle = (e: any) => {
     if (!device) return
     setDevice({ ...device, sleepEnabled: e.detail.value })