Implemented auth system with user model, controller, routes, and tests

[akshayw1]

Title:

Add authentication system with user model,auth controllers, auth routes, auth middlewares and tests

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Description:

Implemented the authentication system with user registration and login functionalities. Added user model, routes for authentication, and necessary test cases to ensure the system works as expected. Included email validation during user registration and login processes, also the documentation, in DOCUMENTION

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Related Issue:

• Feature Request: Integrate User Authentication System for Tracking Personalized Contributions #105

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Motivation and Context:

This change is required to provide a secure authentication mechanism for users. It ensures proper validation of user data (including email) and implements login and registration functionalities.

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Screenshots (In case of UI changes):

N/A (No UI changes were made)

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Types of changes:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

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Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• All new and existing tests have passed and it does not give any unexpected errors for the same.

[akshayw1]

@rajutkarsh07 Please review

[rajutkarsh07]

LGTM