[BE-37] Add document download endpoint with access logging

[mftee]

Overview

Serve original document files to authorized users and log every download for audit purposes inside backend/cmmty/.

Acceptance Criteria

• Create backend/cmmty/document-download/ with module, controller, and service
• Implement GET /cmmty/documents/:id/download protected by JWT guard
• Verify caller is owner or has share permission before serving file
• Log each download: who, when, and from which IP
• Set correct Content-Disposition and Content-Type headers
• Write unit tests for access control and download logging

Contribution Folder

All files must be placed inside backend/cmmty/. Do not modify any file outside this folder.

How to Contribute

Comment on this issue to express interest, fork the repo, build inside backend/cmmty/ only, and open a PR targeting main.

[Clement-coder]

@Clement-coder has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

Hi, I’m a full-stack software engineer with strong experience in secure backend APIs and access control.

I’ll implement the document download module inside backend/cmmty with JWT protection, strict ownership/share checks, and proper file streaming with correct headers. I’ll also add audit logging (user, timestamp, IP) for every download.

Secure, tested, and aligned with project structure.

I can start immediately and deliver quickly.

Would love to be assigned.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Clement-coder to this issue.

[KAMALDEEN333]

@KAMALDEEN333 has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

Hi maintainer am a full stack developer can I work on this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @KAMALDEEN333 to this issue.

[drips-wave]

Congratulations, @KAMALDEEN333! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on April 29, 2026.

🧑‍💻 @KAMALDEEN333: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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[drips-wave]

This issue has been completed by @KAMALDEEN333 as part of the Stellar Wave Program's 4th Wave 🥳

😎 @KAMALDEEN333: You earned 200 Points for completing this issue! After the current Wave ends, you'll be eligible for a percentage of the Wave's reward pool based on the percentage of total points you've earned. Learn more here. You can also Leave a review to share your experience working on this issue.

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