Describe the bug

1. The data from the req.body for the register user controller and login controller are not validated using Joi correctly. The username, email, and password are not correctly extracted from userRegisterSchema.validate.
   After validation, these values should be extracted from userRegisterSchema.validate instead of using variables directly from req.body, since userRegisterSchema.validate contains the sanitized values.

2. The errors are not properly handled. Error handling is mixed between synchronous and asynchronous code. try-catch more consistently. There should be an error check if the error is from Joi or the req.body not only the generic 500 status code error.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'the backend folder'
2. Then go to 'the controllers' folder'
3. Click on 'authController.js'
4. See error

Expected behavior

1. Destructuring userRegisterSchema.validate: After validating the inputs, I destructured the username, email, and password from userRegisterSchema.validate rather than directly from req.body.

2. Proper Error Handling: The try-catch block catches all errors, and I ensure that Joi validation errors are specifically handled using error.isJoi. For other types of errors (such as database-related errors), it logs them and returns a generic server error.

Screenshots before

screenshots after fix*

check list

• I am contributing under GSSoC-ext
• I am contributing under hacktoberfest
• I follow contribution guidlines

Additional context
@divyansh-2005 I want to fix this issue, please let it be assigned to me.