fix(notifications): handle limit=0 in getNotifications query

Replace falsy guards with explicit undefined checks so that a
limit or offset of 0 is not silently discarded.

Signed-off-by: Suhrid Marwah <suhridmarwah07@gmail.com>

plugins/notifications-backend/src/database/DatabaseNotificationsStore.test.ts

@@ -469,6 +469,11 @@ describe.each(databases.eachSupportedId())(
           id3,
         ]);
       });
+
+      it('should return empty array when limit is 0', async () => {
+        const result = await storage.getNotifications({ user, limit: 0 });
+        expect(result).toEqual([]);
+      });
     });
 
     describe('getNotifications sorting', () => {

plugins/notifications-backend/src/database/DatabaseNotificationsStore.ts

@@ -289,11 +289,11 @@ export class DatabaseNotificationsStore implements NotificationsStore {
       }
     }
 
-    if (options.limit) {
+    if (options.limit !== undefined) {
       query.limit(options.limit);
     }
 
-    if (options.offset) {
+    if (options.offset !== undefined) {
       query.offset(options.offset);
     }