[Desktop] Loading screen (#2274)

Co-authored-by: huchenlei <huchenlei@proton.me>

src/views/DesktopStartView.vue

@@ -0,0 +1,13 @@
+<template>
+  <BaseViewTemplate dark>
+    <div class="max-w-screen-sm w-screen p-8">
+      <ProgressBar mode="indeterminate" />
+    </div>
+  </BaseViewTemplate>
+</template>
+
+<script setup lang="ts">
+import ProgressBar from 'primevue/progressbar'
+
+import BaseViewTemplate from './templates/BaseViewTemplate.vue'
+</script>