feat: added refresh token

[MitulSonagara]

📋 Description

Adding a JWT refresh token, In the current situation there is no refresh token for the users, they have to continuously authenticate them selves after 20min of expiration of the token

🔨 Changes Made

✅ Checklist

Before submitting the PR, please make sure you have completed the following:

• I have followed all the guidelines mentioned in CONTRIBUTING.md.
• My code follows the style guidelines of this project.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation (if applicable).
• I have tested it locally and it works fine.
• Any dependent changes have been merged and published in downstream modules.

🏷️ Types of Changes

What type of changes does your code introduce? (Check all that apply)

• Bug fix (non-breaking change which fixes an issue) 🐛

• New feature (non-breaking change which adds functionality) ✨

• UI enhancement (non-breaking change which enhances UI) 🎨

• Documentation update 📚

• Fixes Adding refresh token #105

📸 Screenshots (if applicable)

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Thank you for contributing to Research Nexus! We look forward to reviewing your PR and getting it merged!

[Harshdev098]

Will review Your PR shortly