refactor(frontend): use PageWithHeader instead of MkStickyContainer+MkPageHeader combination

packages/frontend/src/components/global/PageWithAnimBg.vue

@@ -0,0 +1,21 @@
+<!--
+SPDX-FileCopyrightText: syuilo and misskey-project
+SPDX-License-Identifier: AGPL-3.0-only
+-->
+
+<template>
+<div>
+	<MkAnimBg style="position: absolute;"/>
+	<div class="_pageScrollable" style="position: absolute; top: 0; width: 100%; height: 100%;">
+		<slot></slot>
+	</div>
+</div>
+</template>
+
+<script lang="ts" setup>
+import MkAnimBg from '@/components/MkAnimBg.vue';
+</script>
+
+<style lang="scss" module>
+
+</style>