refactor: restructure entire project for human maintainability

Server:
- Add Express framework, replace custom router/request parser
- Create DAO layer (12 files) centralizing all 73 SQL queries
- Rewrite 7 route files as thin Express controllers calling DAOs
- Add SCF-to-Express adapter (lib/serverless.js)
- Add auth middleware (middleware/auth.js)
- Remove dead code from lib/auth.js

Admin console:
- Extract DataTable component (table + pagination)
- Extract ConfirmModal component (modal + form styles)
- Create listMixin for paginated list pages
- Move form styles to common.css for slot compatibility
- Refactor device + subscription pages as examples

Miniprogram:
- Split 734-line BLE monolith into 4 focused modules
  (protocol, connection, commands, barrel index)
- Create API module (utils/api.js) with named functions
- Create page utilities (utils/page.js)
- Refactor index + profile pages to use API module

server/src/routes/user.js

@@ -1,52 +1,45 @@
-const { query } = require('../lib/db')
+const router = require('express').Router()
 const { ok, fail } = require('../lib/response')
-const { requireUser } = require('../lib/auth')
-const { writeLog } = require('../lib/log')
+const { requireUser } = require('../middleware/auth')
 const { getPhoneNumber } = require('../lib/wechat')
+const userDao = require('../dao/user.dao')
+const deviceDao = require('../dao/device.dao')
+const logDao = require('../dao/log.dao')
 
-function register(router) {
-  router.get('/api/v1/user/profile', async ctx => {
-    const user = await requireUser(ctx)
-    if (!user) return fail(1001, 'invalid_token')
-    const binds = await query('SELECT COUNT(*) AS total FROM bindings WHERE user_id = :user_id AND bind_status = 1', { user_id: user.user_id })
-    return ok({
-      user_id: String(user.user_id),
-      nickname: user.nickname || '用户' + String(user.user_id),
-      avatar: user.avatar || '',
-      phone: user.phone || '',
-      gender: user.gender || 0,
-      bind_time: null,
-      device_count: binds[0].total
-    })
+const wrap = fn => (req, res, next) => fn(req, res, next).catch(next)
+
+router.get('/user/profile', requireUser, wrap(async (req, res) => {
+  const user = req.user
+  const devices = await deviceDao.listByUser(user.user_id)
+  res.json(ok({
+    user_id: String(user.user_id),
+    nickname: user.nickname || '用户' + String(user.user_id),
+    avatar: user.avatar || '',
+    phone: user.phone || '',
+    gender: user.gender || 0,
+    bind_time: null,
+    device_count: devices.length
+  }))
+}))
+
+router.put('/user/profile', requireUser, wrap(async (req, res) => {
+  await userDao.updateProfile(req.user.user_id, {
+    nickname: req.body.nickname || null,
+    avatar: req.body.avatar || req.body.avatar_url || null,
+    gender: req.body.gender === undefined ? null : req.body.gender
   })
+  await logDao.write({ user_id: req.user.user_id, action: 'user_update', detail: '更新用户资料', ip: req.ip })
+  res.json(ok({ message: 'success' }))
+}))
 
-  router.put('/api/v1/user/profile', async ctx => {
-    const user = await requireUser(ctx)
-    if (!user) return fail(1001, 'invalid_token')
-    await query('UPDATE users SET nickname = COALESCE(:nickname, nickname), avatar = COALESCE(:avatar, avatar), gender = COALESCE(:gender, gender) WHERE user_id = :user_id', {
-      user_id: user.user_id,
-      nickname: ctx.body.nickname || null,
-      avatar: ctx.body.avatar || ctx.body.avatar_url || null,
-      gender: ctx.body.gender === undefined ? null : ctx.body.gender
-    })
-    await writeLog({ user_id: user.user_id, action: 'user_update', detail: '更新用户资料', ip: ctx.ip })
-    return ok({ message: 'success' })
-  })
+router.post('/user/phone', requireUser, wrap(async (req, res) => {
+  const code = String(req.body.code || '').trim()
+  if (!code) return res.json(fail(2001, 'phone code required'))
+  const phoneInfo = await getPhoneNumber(code)
+  if (!phoneInfo || !phoneInfo.phoneNumber) return res.json(fail(2001, 'phone authorization failed'))
+  await userDao.updatePhone(req.user.user_id, phoneInfo.phoneNumber)
+  await logDao.write({ user_id: req.user.user_id, action: 'user_phone_bind', detail: '授权手机号', ip: req.ip })
+  res.json(ok({ phone: phoneInfo.phoneNumber, pure_phone_number: phoneInfo.purePhoneNumber || '', country_code: phoneInfo.countryCode || '' }))
+}))
 
-  router.post('/api/v1/user/phone', async ctx => {
-    const user = await requireUser(ctx)
-    if (!user) return fail(1001, 'invalid_token')
-    const code = String(ctx.body.code || '').trim()
-    if (!code) return fail(2001, 'phone code required')
-    const phoneInfo = await getPhoneNumber(code)
-    if (!phoneInfo || !phoneInfo.phoneNumber) return fail(2001, 'phone authorization failed')
-    await query('UPDATE users SET phone = :phone WHERE user_id = :user_id', {
-      user_id: user.user_id,
-      phone: phoneInfo.phoneNumber
-    })
-    await writeLog({ user_id: user.user_id, action: 'user_phone_bind', detail: '授权手机号', ip: ctx.ip })
-    return ok({ phone: phoneInfo.phoneNumber, pure_phone_number: phoneInfo.purePhoneNumber || '', country_code: phoneInfo.countryCode || '' })
-  })
-}
-
-module.exports = register
+module.exports = router