Feat/logout

[nafiuishaaq]

I've implemented the logout functionality with the following changes:

1. Created Authentication Middleware (src/middlewares/auth.js)
   Verifies JWT tokens from the Authorization header
   Validates that the token is an access token (not refresh token)
   Attaches the user object and userId to the request
2. Added Logout Controller (src/controllers/auth.controller.js)
   Added the logout function that:
   Gets the authenticated user's ID from the request
   Finds the user in the database
   Clears the refreshTokenHash and refreshTokenExpiresAt fields
   Returns a 200 OK response
3. Added Logout Route (src/routes/auth.routes.js)
   Added POST /api/auth/logout endpoint
   Protected by the authenticate middleware
   Calls the logout controller
   API Endpoint
   POST /api/auth/logout
   Headers: Authorization: Bearer <access_token>
   Response: 200 OK with message "Logout successful"
   The logout endpoint securely invalidates the user's session by clearing the stored refresh token hash from the database, preventing any future token refresh attempts.

Closes #24

[ayshadogo]

@nafiuishaaq
Please resolve conflicts

[nafiuishaaq]

Resolved sir @ayshadogo