Add webhook event replay and delivery-log retention UI

[nanaf6203-bit]

Context

WebhooksService records WebhookDeliveryLog and admin queue endpoints exist, but there's no way to replay a failed event payload or prune old delivery logs; retention is unbounded.

Problem

Support workflows (docs/Handle_Support.md) need 're-send last event' without re-triggering underlying mutations; unbounded logs bloat the DB (see webhook index issue).

Proposed approach

Add POST /webhooks/:id/:deliveryId/replay (re-sends stored payload with same idempotency key), a payload size cap warning, and retention pruning in CleanupService for WebhookDeliveryLog (env CLEANUP_WEBHOOK_LOG_DAYS).

Acceptance criteria

• Replay + retention are user-visible and tested.

[VeronicDev]

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

Hello Maintainer, I can fix this please assign.

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

[harmondconsultant-png]

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

hy, i can work on it pleas assign

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

[johniloo]

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

Hi Maintainer, I’ve evaluated the scope and am ready to submit a PR once assigned. Please pass this issue my way.

Give me this chance.

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

[B3N-max]

@B3N-max has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hi Maintainer
please kindly assign me this issue to work on
i have critically review this acceptance criteria

ℹ️ Repo Maintainers: To accept this application, review their application or assign @B3N-max to this issue.

[drips-wave]

Congratulations, @B3N-max! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on September 30, 2026.

🧑‍💻 @B3N-max: 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

When opening a PR, please link it to this issue to ensure it gets tracked accurately. Points are awarded when this issue is marked as completed by the maintainer.

🤠 Repo maintainers: Please keep an eye on the contributor's progress and review their work before the due date. You can manage this issue, including adjusting its complexity and points, here.

🌊 Happy Wave 🌊