fix: use node engine range instead of exact version

[TechGenius-Karan]

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🔍 Description

I simply updated the package-json file and used node engine range instead of an exact version

Closes #BUG-018 (if applicable)

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✅ Checklist

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• Verified that the project builds and runs locally (npm run dev)
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• Updated documentation, comments, or in-code explanations where needed
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• Followed the CONTRIBUTING.md guidelines

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📂 Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to change)
• 📝 Documentation update
• ♻️ Refactor / code quality improvement
• 🎨 UI/UX enhancement
• 🔒 Security improvement

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🧩 Additional Notes for Reviewers

[TechGenius-Karan]

@all-contributors please add @TechGenius-Karan for code, bug

[allcontributors]

@TechGenius-Karan

I've put up a pull request to add @TechGenius-Karan! 🎉