feat: notification service has_unread_notification 메서드 추가

pennyway-app-external-api/src/main/java/kr/co/pennyway/api/apis/notification/service/NotificationSearchService.java

@@ -19,4 +19,9 @@ public class NotificationSearchService {
     public Slice<Notification> getNotifications(Long userId, Pageable pageable) {
         return notificationService.readNotificationsSlice(userId, pageable);
     }
+
+    @Transactional(readOnly = true)
+    public boolean hasUnreadNotification(Long userId) {
+        return notificationService.readUnreadNotification(userId);
+    }
 }

pennyway-domain/src/main/java/kr/co/pennyway/domain/domains/notification/service/NotificationService.java

@@ -37,6 +37,11 @@ public Slice<Notification> readNotificationsSlice(Long userId, Pageable pageable
         return SliceUtil.toSlice(notificationRepository.findList(predicate, queryHandler, sort), pageable);
     }
 
+    @Transactional(readOnly = true)
+    public boolean readUnreadNotification(Long userId) {
+        return notificationRepository.existsTopByReceiver_IdAndReadAtIsNull(userId);
+    }
+
     @Transactional(readOnly = true)
     public long countUnreadNotifications(Long userId, List<Long> notificationIds) {
         return notificationRepository.countUnreadNotificationsByIds(userId, notificationIds);