feat(user): add UserController for managing user operations

[Lapotor]

Introduce the UserController to handle the following user-related functionalities:

• Retrieve all users
• Display details of a specific user
• Create a new user
• Update existing user information
• Delete a user

---

Needs:

• fix(requests): update request handling and non-json request testing #74

Closes:

• Close Implement GET /users Endpoint for returning a list of all registered users. #10
• Close Implement POST /users Endpoint for creating a new user. #11
• Close Implement GET /users/{id} Endpoint for getting a user by ID. #12
• Close Implement PUT /users/{id} Endpoint for updating a user by ID. #13
• Close Implement DELETE /users/{id} Endpoint for deleting a user by ID. #14