feat(frontend): 通知の表示をカスタマイズできるように

packages/frontend/src/store.ts

@@ -314,6 +314,14 @@ export const defaultStore = markRaw(new Storage('base', {
 		where: 'device',
 		default: 'expand' as 'expand' | '16_9' | '1_1' | '2_3',
 	},
+	notificationPosition: {
+		where: 'device',
+		default: 'rightBottom' as 'leftTop' | 'leftBottom' | 'rightTop' | 'rightBottom',
+	},
+	notificationStackAxis: {
+		where: 'device',
+		default: 'horizontal' as 'vertical' | 'horizontal',
+	},
 }));
 
 // TODO: 他のタブと永続化されたstateを同期