fix: 修正 main.js 为 uni-app 3.x 写法

src/main.js

@@ -1,11 +1,9 @@
-import Vue from 'vue'
+import { createSSRApp } from 'vue'
-import App from './App'
+import App from './App.vue'
 
-Vue.config.productionTip = false
+export function createApp() {
-
+  const app = createSSRApp(App)
-App.mpType = 'page'
+  return {
-
+    app
-const app = new Vue({
+  }
-  ...App
+}
-})
-app.$mount()