Indexer: add cursor checkpoint integrity checks

[Otaiki1]

Build location

Work primarily in indexer/src/ingestor/cursor-manager.service.ts. Keep related tests/docs beside that package unless this issue explicitly calls for a cross-package update.

Why this matters

Cursor state is critical and should include ledger hash, sequence, processed event count, and monotonicity checks.

What to build

• Extend cursor manager validation before save and on startup.
• Detect ledger hash mismatch and sequence regression.
• Expose checkpoint details in status command.

Acceptance criteria

• Tests cover normal advance, duplicate ledger, hash mismatch, and regression.
• Invalid cursor state sends ingestion to safe paused/degraded mode.

Suggested verification

cd indexer && npm run lint && npm run test && npm run build

[ObaniIsola]

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

Good Morning Ser, I'm a seasoned and well-experienced senior developer. I want to take up this issue and solve it accurately.

Thank you as you grant my request.

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[Emelie-Dev]

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

Hi, I would love to work on this issue.

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[raizo07]

@raizo07 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hello, kindly assign me to work on this issue

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[Awointa]

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

Hi, I’m interested in this issue. I have experience building resilient indexing and ingestion systems with checkpoint validation, cursor integrity handling, and recovery-safe processing flows.

I can extend the cursor manager to validate ledger hashes, sequence monotonicity, and processed event counts both during startup and before checkpoint persistence. I’ll also add safe degraded/paused handling for invalid cursor states, expose checkpoint metadata in the status flow, and include comprehensive tests covering duplicate ledgers, regressions, and hash mismatch scenarios.

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

[drips-wave]

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

🧑‍💻 @Awointa: 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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