refactor(frontend): ID生成処理を統一

packages/frontend/src/pages/settings/preferences.vue

@@ -796,6 +796,7 @@ import { globalEvents } from '@/events.js';
 import { claimAchievement } from '@/utility/achievements.js';
 import { instance } from '@/instance.js';
 import { ensureSignin } from '@/i.js';
+import { genId } from '@/utility/id.js';
 
 const $i = ensureSignin();
 
@@ -1009,7 +1010,7 @@ let smashTimer: number | null = null;
 
 function testNotification(): void {
 	const notification: Misskey.entities.Notification = {
-		id: Math.random().toString(),
+		id: genId(),
 		createdAt: new Date().toUTCString(),
 		isRead: false,
 		type: 'test',