Add the register route for locally register user and test the applicatio

[Deepak-cell311]

Description

This pull request adds a new /register route to allow local user registration (not via third-party auth). It includes the necessary controller logic, model validation, and route integration. Additionally, basic tests have been conducted to ensure the registration flow works as expected.

Related Issues

Closes #1248

Steps to Test

1. Run the development server : npm run dev

2. Send a POST request to: http://localhost:3000/api/auth/register

3. Body payload example (JSON):

   {
      "name": "Test User",
      "email": "[email protected]",
      "password": "test123"
   }
   
   

4. Check the response and ensure the user is saved to the database.

5. Try registering with an existing email to test validation.

Screenshots

Before

After

Checklist

• I have tested these changes
• I have updated the relevant documentation
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the codebase
• My changes generate no new warnings or errors
• The title of my pull request is clear and descriptive

[Deepak-cell311]

Hi @salahlalami
Kindly have a look over and review this PR whenever you have a moment.
Thank you🚀