Improve Scalability for Large User Base

**Description:**
The current version of the LibraryMan application is not optimized to handle a large number of users simultaneously, leading to performance bottlenecks when there is high traffic. The system needs to be refactored to improve scalability and efficiently handle a very large amount of traffic.

**Task:**
- Analyze the current architecture and identify potential bottlenecks.
- Perform stress tests to confirm improvements.

**Acceptance Criteria:**
- The system should be able to handle a significantly higher number of concurrent users without performance degradation.
- Document any architectural changes made to improve scalability.
- The application passes stress tests simulating high traffic scenarios.