refactor：项目升级Vue3+uView Plus

- 改造入口文件、全量替换组件引入
- 过滤器迁移混入，更新忽略配置，新增迁移文档

pages/tabbar/home/template/tpl_flex_three.vue

@@ -2,7 +2,7 @@
 <template>
   <div class="layout">
     <u-image @click="modelNavigateTo(item)" height="240rpx" width="240rpx" class="image-mode" :src="item.img" v-for="(item, index) in res.list" :key="index">
-      <u-loading slot="loading"></u-loading>
+      <template #loading><u-loading></u-loading></template>
     </u-image>
   </div>
 </template>