feature: added Hardhat test file for smart contract

[SIDDHANTCOOKIE]

Summary

Hey @karthiksathishjeemain and @pradeeban this PR introduces Hardhat based smart contract testing to the project.

It adds an initial test suite for the smart contract and sets up the required Hardhat configuration so contributors can run tests locally in a consistent and reproducible way.

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What’s included

• Added Hardhat configuration for smart contract development and testing
• Added initial smart contract test file
• Added package.json and package-lock.json to include required Hardhat dependencies
• Updated .gitignore to exclude Hardhat generated folders (artifacts and cache)

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Why this change

Before this PR, the repository did not have a standard setup for smart contract testing.

This change ensures that anyone cloning the repo can run:

npm install
npx hardhat test

Note to Maintianers

This PR includes changes to both package.json and package-lock.json as well for the newly added Hardhat setup. Please let me know if you’d prefer excluding these files, and I’ll update the PR accordingly.

Closes #116
Awaiting Review, Thanks.