Add indexer cursor stale-age warning threshold config

[Chucks1093]

Summary
Add indexer cursor stale-age warning threshold config

Scope

• add configurable threshold for stale indexer cursor age warnings\n- emit warning when threshold is exceeded\n- document default threshold and override

Acceptance Criteria

• scoped change is implemented with no unrelated file churn
• docs/tests are updated where applicable
• contributor can validate the outcome locally

Contributor coordination: if you pick this up, reach out in Telegram for updates or clarification: https://t.me/accesslayerorg

[samjay8]

@samjay8 has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

Let me handle this task for you, Chief. I will deliver fastt

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[harystyleseze]

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

i would like to work on this

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[ONEONUORA]

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

Hi , I am a backend developer with 3 years of experience. I believe i can handle this issue

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

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[drips-wave]

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

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