refactor: update UserEntity to allow onlineAt to be nullable and enhance sorting logic in UsersRepository

- Changed onlineAt property in UserEntity to be nullable.
- Updated sorting logic in UsersRepository to include subRevokedAt in the dateFields array.

Author: kastov

src/modules/users/entities/users.entity.ts

@@ -17,7 +17,7 @@ export class UserEntity implements Users {
     public subLastOpenedAt: Date;
 
     public expireAt: Date;
-    public onlineAt: Date;
+    public onlineAt: Date | null;
     public subRevokedAt: Date | null;
     public lastTrafficResetAt: Date | null;
 

src/modules/users/repositories/users.repository.ts

@@ -362,10 +362,9 @@ export class UsersRepository implements ICrud<UserEntity> {
 
         let orderBy = sorting?.reduce((acc, sort) => {
             const dateFields = [
-                'expireAt',
-                'createdAt',
                 'lastTrafficResetAt',
                 'subLastOpenedAt',
+                'subRevokedAt',
                 'onlineAt',
             ];