fix(indexer): increase reconciler ledger throughput (currently max 50 ledgers/cycle)

[cypriannwokolo2-creator]

Summary

indexer/reconciler.go:95 processes at most 50 ledgers per cycle; a large gap takes many 5-minute intervals to catch up, and the cursor advances only after each ledger.

Acceptance Criteria

• Configurable batch size, bounded per cycle
• Parallel-safe cursor advancement
• Backfill test

Complexity

High.

[ghost-cy829]

@ghost-cy829 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I would like to work on this issue. I have experience with Rust and Soroban smart contract development. I will follow the acceptance criteria and add tests. Excited to contribute. Kindly assign.

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[Gabbydunkk]

@Gabbydunkk has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Pls assign to me

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Congratulations, @Gabbydunkk! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

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This issue has been completed by @Gabbydunkk as part of the Stellar Wave Program's 8th Wave 🥳

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