Add e-commerce demo application using Valkey

[Jaithra2104]

This PR introduces a complete e-commerce demo application built with Node.js and Express, showcasing Valkey for cart management, session storage, product caching, real-time inventory, and search functionalities.

Buildathon Submission Pull Request

Thank you for submitting your project for the Build Beyond Limits 2.0 - powered by Valkey and Breeth AI, hosted by React Hyderabad.

Please fill in the details below before raising your Pull Request.

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Submission Details

Project Name: ValkeyCommerce
Attendee Name: Addepalli Jaithra Srivaatsava
Problem Statement Selected: statement no:60

Choose one:

• HR Cost Intelligence Engine
• Intelligent Slack Knowledge Base

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Checklist

Please confirm the following:

• [ yes] I have created my submission file inside the submissions/ folder.
• [yes ] My submission file follows this naming format: projectname_attendeeName.md.
• [ yes] I have used the SUBMISSION_TEMPLATE.md format.
• [ no] I have added my GitHub project repository link.
• [no ] I have added my LinkedIn profile link.
• [ no] I have added my GitHub username.
• [no ] My project repository is public.
• [no ] I have not added API keys, passwords, tokens, or private credentials.
• I understand that my actual project code should be in my own GitHub repository, not in this repository.

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Project Repository Link

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