Fix: Resolved all Netlify deployment issues in MERN Shopping List project

[Sameer-Malik20]

Summary

This PR fixes all deployment-related issues that were preventing the MERN Shopping List project from running properly on Netlify.

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Fixes Included

• Replaced unsupported ES module directory imports (e.g., changed import config to import config from './config/index.js')
• Ensured correct proxy configuration for frontend/backend communication
• Removed or replaced any local-specific paths not supported in Netlify's build environment
• Verified build success on Netlify and tested full frontend-backend functionality

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Testing & Deployment

• App now deploys successfully on Netlify
• All features work as expected (login/logout, adding/deleting items, etc.)
• UI is responsive and bug-free

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✅ Ready for review. Let me know if any changes are needed.
Live Preview: https://funny-baklava-10d1b5.netlify.app