refactor(app): 重构应用主题和页面结构

- 移除动态主题切换功能，改为全局统一深色主题
- 实现自定义TabBar组件替换原生tabBar，解决iOS闪白问题
- 创建main容器页面统一管理三个tab页面的生命周期和状态
- 将所有页面的onShow/onHide等生命周期方法迁移到子组件内部
- 更新页面路径从index改为main，并调整路由跳转逻辑
- 移除theme-mixin和相关主题工具函数
- 统一页面背景色设置，优化用户体验一致性

pages/profile/profile.vue

@@ -1,5 +1,5 @@
 <template>
-  <view :class="themeClass" class="page-container profile-page">
+  <view class="page-container profile-page">
     <!-- 沉浸式头部 -->
     <view class="hero-header" :style="{ paddingTop: headerPaddingTop }">
       <view class="hero-bg">
@@ -176,11 +176,11 @@ import AchievementBadge from '../../components/AchievementBadge.vue'
 import client, { clearAuth, GetAchievements, isLoggedIn, requireLogin } from '../../common/api'
 import { checkAchievements, getCatIcon, isIconPath, calcLocalStreak, isValidAvatar } from '../../common/utils'
 import { ACHIEVEMENTS, DRINK_CATEGORIES } from '../../common/constants'
-import themeMixin from '../../common/theme-mixin'
 
 export default {
-  mixins: [themeMixin],
   components: { AchievementBadge },
+  // Vue3 组件事件必须显式声明
+  emits: ['switch-tab'],
   data() {
     // 获取胶囊按钮位置，动态计算分享按钮偏移和头部内边距
     const sysInfo = uni.getSystemInfoSync()
@@ -252,25 +252,26 @@ export default {
       return '百天老友，酒中见真章'
     }
   },
-  onShow() {
-    this.checkLoginState()
-    this.loadData()
-  },
-  onShareAppMessage() {
-    const name = this.user.nickname || '我'
-    return {
-      title: `${name}的饮酒名片 - 碰盏日记`,
-      path: `/pages/share-profile/share-profile?${this.buildShareQuery()}`
-    }
-  },
-  onShareTimeline() {
-    const name = this.user.nickname || '我'
-    return {
-      title: `${name}的饮酒名片 - 碰盏日记`,
-      query: this.buildShareQuery()
-    }
-  },
   methods: {
+    // === 子组件生命周期（由 main.vue 容器通过 ref 调用）===
+    pageShow() {
+      this.checkLoginState()
+      this.loadData()
+    },
+    getShareAppMessage() {
+      const name = this.user.nickname || '我'
+      return {
+        title: `${name}的饮酒名片 - 碰盏日记`,
+        path: `/pages/share-profile/share-profile?${this.buildShareQuery()}`
+      }
+    },
+    getShareTimeline() {
+      const name = this.user.nickname || '我'
+      return {
+        title: `${name}的饮酒名片 - 碰盏日记`,
+        query: this.buildShareQuery()
+      }
+    },
     isValidAvatar,
     isIconPath,
     // 构建分享名片的 query 参数（携带公开档案数据）
@@ -382,13 +383,13 @@ export default {
       return ACHIEVEMENTS[index % ACHIEVEMENTS.length].icon
     },
     goCircle() {
-      uni.switchTab({ url: '/pages/circle/circle' })
+      this.$emit('switch-tab', 1)
     },
     goGames() {
       uni.navigateTo({ url: '/pages/games/games' })
     },
     goHome() {
-      uni.switchTab({ url: '/pages/index/index' })
+      this.$emit('switch-tab', 0)
     },
     goRecord() {
       if (!requireLogin()) return