fix(frontend): popupのemit型が正しく利用できるように修正 (#16826)

* fix(frontend): popupのemit型が正しく利用できるように修正

* fix: revert unnecessary code (for testing purpose)

* fix lint

* fix type errors

* fix types

* add comment

* fix

* fix

* fix: OverloadToUnionの仕組みを変更

* add comments, clean up

* fix lint

* fix types

* clean up [ci skip]

* fix

* add comments [ci skip]

packages/frontend/src/components/MkUpdated.vue

@@ -4,7 +4,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 -->
 
 <template>
-<MkModal ref="modal" preferType="dialog" :zPriority="'middle'" @click="modal?.close()" @closed="$emit('closed')">
+<MkModal ref="modal" preferType="dialog" :zPriority="'middle'" @click="modal?.close()" @closed="emit('closed')">
 	<div :class="$style.root">
 		<div :class="$style.title"><MkSparkle>{{ i18n.ts.misskeyUpdated }}</MkSparkle></div>
 		<div :class="$style.version">✨{{ version }}🚀</div>
@@ -26,6 +26,10 @@ import { confetti } from '@/utility/confetti.js';
 
 const modal = useTemplateRef('modal');
 
+const emit = defineEmits<{
+	(ev: 'closed'): void;
+}>();
+
 const isBeta = version.includes('-beta') || version.includes('-alpha') || version.includes('-rc');
 
 function whatIsNew() {