Enhancement: Implement Helmet and HPP for security (#56)

[100NikhilBro]

Security Improvement Suggestion

Summary

This PR enhances backend security by adding helmet and hpp middlewares.

Implemented Changes

• Added a centralized security middleware (middleware/security.js)
• Configured Helmet for secure HTTP headers
• Configured HPP to prevent HTTP parameter pollution
• Disabled Express 'x-powered-by' header
• Ensured frontend compatibility (CSP and COEP disabled)

Why

Improves API resilience and prevents common web vulnerabilities as discussed in Issue #56.

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[100NikhilBro]

Hi @Avdhesh-Varshney @archa8,
I’ve created the PR. Please review it whenever you get a chance and let me know if any improvements are needed. 😊

[archa8]

I have left a comment on server.js. Kindly make the respective changes.

[Avdhesh-Varshney]

@100NikhilBro I think for CSP and Origin, You should use valid values instead disabling them. First test so that FE doesn't break.

[100NikhilBro]

@Avdhesh-Varshney Got it! Yeah, you’re right — I’ll test it properly to ensure the FE doesn’t break. I’ll check everything in the next 2–3 days and update the PR accordingly. 👍