Introduce cursor-based pagination for the user search functionality to allow searching beyond the current 10,000 user limit.

Background:
Currently, the user search functionality is limited to indexing and searching up to 10,000 users due to the constraints of index-based pagination. This problem is tracked by CONFCLOUD-77805 - The "rest/api/search/user" API doesn't return any value above 9999 count. This limitation poses challenges for organizations with large user bases, restricting their ability to perform comprehensive searches and manage user data effectively.

Problem Statement:
The existing index-based pagination system imposes a hard limit of 10,000 users that can be searched. This limitation hinders user experience and operational efficiency for large organizations that need to access and manage a more extensive user list. As our user base continues to grow, this limitation becomes increasingly problematic.

Proposed Solution:
Implement a cursor-based pagination system for the user search functionality. Cursor-based pagination allows for efficient traversal of large datasets without being constrained by a fixed limit, thereby enabling users to search through more than 10,000 users seamlessly.