Add environment-specific CSP headers for dev and prod

[Akatenvictor]

What

Configure different Content Security Policy headers for development and production environments to accommodate development tools while maintaining security in production.

Why

Development requires relaxed CSP (hot module replacement, dev tools, localhost connections) while production needs strict CSP. Using the same CSP in both environments either breaks dev or weakens prod security.

Scope

In scope:

• Development CSP: allow localhost, eval (for HMR), inline scripts
• Production CSP: strict source restrictions, no eval, no inline
• Configuration through Next.js middleware or config
• CSP report-only mode for initial deployment

Out of scope:

• CSP violation reporting endpoint
• Modifying application code for CSP
• Subresource integrity (SRI) setup

Acceptance Criteria

• Development CSP allows HMR and dev tools
• Production CSP restricts all sources
• No CSP violations in development mode
• No CSP violations in production mode
• CSP headers are present in HTTP responses

Technical Context

• Next.js config at app/next.config.js
• Middleware at app/src/middleware.ts

[Power70]

@Power70 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi Maintainer,
I can work on this issue.
Kindly assign it to me.
Thank you

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[ada-nwali]

@Ada-Girly881 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I'm a full-stack blockchain developer and active open-source contributor interested in tackling this issue. My experience spans smart contract development and frontend/backend integration, which aligns well with Drips' stack.

I've contributed to OSS projects and I'm comfortable navigating unfamiliar codebases, writing clean and tested code, and collaborating through PRs and reviews.

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[Queen-T16]

@Queen-T16 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hello maintainer, i would like to work on this issue

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[drips-wave]

Congratulations, @Queen-T16! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

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This issue has been completed by @Queen-T16 as part of the Stellar Wave Program's 7th Wave 🥳

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[Divine639700]

@Divine639700 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi maintainer based on my experiences as a computer software developer I think I am very much capable to handle the given task

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