Backend: expand maintenance mode with scoped degradation

[Otaiki1]

Build location

Work primarily in backend/src/maintenance. Keep related tests/docs beside that package unless this issue explicitly calls for a cross-package update.

Why this matters

Maintenance mode should allow disabling risky write paths while keeping safe read paths available.

What to build

• Extend maintenance-mode service/guard to support scopes such as all, writes, raffles, notifications, monitor.
• Add route metadata or decorators for scoped behavior.
• Return retry guidance to clients.

Acceptance criteria

• Tests cover each scope and skip-maintenance decorator behavior.
• Docs list supported maintenance scopes and example env/config.

Suggested verification

cd backend && npm run lint && npm run test && npm run build

[larryjay007]

@larryjay007 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi, can I work on this?

ℹ️ Repo Maintainers: To accept this application, review their application or assign @larryjay007 to this issue.

[drips-wave]

Congratulations, @larryjay007! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @larryjay007: 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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