fix: storagePersistenceのtop-level awaitを解消

packages/frontend/src/boot/common.ts

@@ -30,6 +30,7 @@ import { fetchCustomEmojis } from '@/custom-emojis.js';
 import { prefer } from '@/preferences.js';
 import { $i } from '@/i.js';
 import { launchPlugins } from '@/plugin.js';
+import { initializeStoragePersistence } from '@/utility/storage.js';
 
 export async function common(createVue: () => Promise<App<Element>>) {
 	console.info(`Misskey v${version}`);
@@ -327,6 +328,10 @@ export async function common(createVue: () => Promise<App<Element>>) {
 		console.error('Failed to launch plugins:', error);
 	}
 
+	// ブラウザストレージ永続化の状態を初期化
+	// （top-level awaitを防ぐために明示的に起動時に確認する）
+	initializeStoragePersistence();
+
 	app.mount(rootEl);
 
 	// boot.jsのやつを解除

packages/frontend/src/utility/storage.ts

@@ -3,20 +3,27 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-import { ref } from 'vue';
+import { readonly, ref } from 'vue';
 import * as os from '@/os.js';
 import { store } from '@/store.js';
 import { i18n } from '@/i18n.js';
 
 export const storagePersistenceSupported = window.isSecureContext && 'storage' in navigator;
-export const storagePersisted = ref(storagePersistenceSupported ? await navigator.storage.persisted() : false);
+const _storagePersisted = ref(false);
+export const storagePersisted = readonly(_storagePersisted);
+
+export async function initializeStoragePersistence() {
+	if (storagePersistenceSupported) {
+		_storagePersisted.value = await navigator.storage.persisted().catch(() => false);
+	}
+}
 
 export async function enableStoragePersistence() {
 	if (!storagePersistenceSupported) return;
 	try {
 		const persisted = await navigator.storage.persist();
 		if (persisted) {
-			storagePersisted.value = true;
+			_storagePersisted.value = true;
 		} else {
 			os.alert({
 				type: 'error',