[BE-38] Implement real-time WebSocket notifications

[mftee]

Overview

Use WebSockets to push instant updates to users when their document status changes or a verification completes inside backend/cmmty/.

Acceptance Criteria

• Create backend/cmmty/realtime/ with a NestJS WebSocket Gateway (socket.io)
• Authenticate WebSocket connections using the existing JWT token
• Emit document.status_changed event when a document status updates
• Emit verification.complete event when Stellar anchor succeeds
• Write unit tests for event emission logic

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.

[feyishola]

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

Hi, im Feyishola, a software developer with over 4 years of experience. Please i would like to handle this issue

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

[drips-wave]

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

🧑‍💻 @feyishola: 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.

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[drips-wave]

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

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