feat: add registration page for new miniprogram users

- New register page with chooseAvatar, nickname input (random default),
  and required phone number authorization via getPhoneNumber
- Login simplified: removed deprecated wx.getUserProfile, checks
  is_new_user flag to redirect new users to registration
- Server login response now includes is_new_user field

miniprogram/pages/register/register.js

@@ -0,0 +1,102 @@
+var app = getApp()
+var http = require('../../utils/request')
+
+var DEFAULT_AVATAR = 'https://mmbiz.qpic.cn/mmbiz/icTdbqWNOwNRna42FI9t2NHfLvvMiaiaCJQn3KP2P0vAHp1QBP0piavhGfhKCARlGd6z1EbR58ibJXKCp5WVlNnojwA/640'
+
+function randomNickname() {
+  var digits = ''
+  for (var i = 0; i < 4; i++) {
+    digits += Math.floor(Math.random() * 10)
+  }
+  return '用户' + digits
+}
+
+Page({
+  data: {
+    statusBarHeight: 44,
+    loading: false,
+    avatarUrl: DEFAULT_AVATAR,
+    nickname: '',
+    phone: ''
+  },
+
+  onLoad: function () {
+    this.setData({
+      statusBarHeight: app.globalData.statusBarHeight,
+      nickname: randomNickname()
+    })
+  },
+
+  onChooseAvatar: function (e) {
+    if (e.detail && e.detail.avatarUrl) {
+      this.setData({ avatarUrl: e.detail.avatarUrl })
+    }
+  },
+
+  onNicknameInput: function (e) {
+    this.setData({ nickname: e.detail.value || '' })
+  },
+
+  onNicknameBlur: function (e) {
+    var val = (e.detail.value || '').trim()
+    if (!val) {
+      this.setData({ nickname: randomNickname() })
+    } else {
+      this.setData({ nickname: val })
+    }
+  },
+
+  onGetPhoneNumber: function (e) {
+    var self = this
+    if (!e.detail || !e.detail.code) {
+      wx.showToast({ title: '需要授权手机号才能完成注册', icon: 'none' })
+      return
+    }
+    self.setData({ loading: true })
+    http.post('/api/v1/user/phone', { code: e.detail.code }).then(function (data) {
+      self.setData({
+        loading: false,
+        phone: data.phone || data.pure_phone_number || '已授权'
+      })
+      wx.showToast({ title: '手机号授权成功', icon: 'success' })
+    }).catch(function (err) {
+      self.setData({ loading: false })
+      wx.showToast({ title: err.message || '手机号授权失败', icon: 'none' })
+    })
+  },
+
+  onSubmit: function () {
+    var self = this
+    var nickname = (self.data.nickname || '').trim()
+    var avatarUrl = self.data.avatarUrl
+
+    if (!self.data.phone) {
+      wx.showToast({ title: '请先授权手机号', icon: 'none' })
+      return
+    }
+
+    if (!nickname) {
+      wx.showToast({ title: '请输入昵称', icon: 'none' })
+      return
+    }
+
+    self.setData({ loading: true })
+
+    http.put('/api/v1/user/profile', {
+      nickname: nickname,
+      avatar: avatarUrl !== DEFAULT_AVATAR ? avatarUrl : ''
+    }).then(function () {
+      return app.loadProfile()
+    }).then(function () {
+      self.setData({ loading: false })
+      wx.switchTab({ url: '/pages/index/index' })
+    }).catch(function (err) {
+      self.setData({ loading: false })
+      wx.showToast({ title: err.message || '保存失败', icon: 'none' })
+    })
+  },
+
+  onAgreement: function () {
+    wx.showModal({ title: '提示', content: '用户协议和隐私政策内容建设中', showCancel: false })
+  }
+})