Revert "enhance(frontend): '계절에 따른 화면 연출' 기능을 디바이스에 따라 자동으로 활성화하도록 변경함"

This reverts commit 6c20139acf.

packages/frontend/src/store.ts

@@ -435,7 +435,7 @@ export const defaultStore = markRaw(new Storage('base', {
 	},
 	enableSeasonalScreenEffect: {
 		where: 'device',
-		default: !/mobile|iphone|android/.test(navigator.userAgent.toLowerCase()),
+		default: false,
 	},
 	showUnreadNotificationsCount: {
 		where: 'deviceAccount',