Add event-processing metrics endpoint and monitoring support

[robertocarlous]

Summary

The Stellar event listener tracks internal metrics, but there is no dedicated endpoint or monitoring integration for them.

Problem

Operational visibility is limited and it is hard to detect event processing health issues.

Proposed work

• Expose metrics from src/stellar/events.ts via an API route (e.g. /api/stellar/metrics)
• Include metrics like totalProcessed, errorRate, ledgerLag, processingRatePerMinute
• Document monitoring requirements and attach metrics to alert rules
• Add tests for the metrics endpoint

Files

• src/stellar/events.ts
• src/routes/stellar.ts or existing router
• docs for monitoring / src/agent/README.md

Acceptance criteria

• Metrics endpoint is available and returns current event metrics
• Metrics are usable by monitoring tools
• Tests cover endpoint response shape

[somotochukwu-dev]

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

Hi
Please I would like to work on this issue, please assign this issue to me
Thanks.

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

[Xaxxoo]

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

Hi can I work on this issue ?

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

[drips-wave]

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

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