Add GossipsWorld authentication project

[harikanagineni11]

Description

This PR adds a new project Gossip World, a backend-focused Node.js application that demonstrates secure authentication and authorization.

The project allows users to:

• Sign up and log in using hashed passwords
• Authenticate using JWT stored in HTTP-only cookies
• Create, view, edit, and delete their own posts
• Prevent duplicate form submissions using the Post-Redirect-Get pattern

The main focus of this project is backend security and access control, with a simple UI for functionality demonstration.

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Checklist

• [ x] I've been assigned an issue related to this PR.
• [ x] I've used beautifiers.
• [ x] I've added my Project's name and description to Index.md
• I've made a README.md file for my Project.
• The README.md file of my project contains Project title, Description, Use of project, Set up, Stack used and Output (Screenshots).

Related Issues or Pull Requests number

N/A