Refactor Backend Authentication Logic

[galafis]

---

name: User Story
about: This template defines a user story
title: 'Refactor Backend Authentication Logic'
labels: 'technical debt'
assignees: ''

---

As a Developer
I need To refactor the authentication routes (authRoutes.js) to improve code structure and error handling.
So that The codebase is easier to maintain, debug, and extend in the future.

Details and Assumptions

* Current `authRoutes.js` handles registration, login, and update logic directly within the route handlers.
* Consider moving database interaction logic to separate service/controller functions.
* Improve consistency in error responses and logging.
* Review JWT generation and validation process for potential improvements or security best practices.
* Add unit tests for the authentication logic.

Acceptance Criteria

Given the existing authentication logic in `authRoutes.js`
When the refactoring is complete
Then the core functionality (register, login, update) remains unchanged
And the code is organized into smaller, more manageable functions/modules
And error handling is consistent across different scenarios
And unit tests cover the main authentication flows