Build invoice payment reconciler

[Kingsman-99]

Label: complexity: high
Points: 200

Description

The funded amount on an invoice may drift from the sum of individual payment records due to edge cases. This issue adds reconcilePayments(invoiceId) that fetches both the invoice state and all payment events, detects discrepancies, and returns a typed reconciliation report.

Technical Context

Involves a new src/reconciler.ts. Fetch invoice via getInvoice and payments via getPayments. Sum payment amounts and compare to invoice.funded. Define ReconciliationReport = { invoiceId: string; invoiceFunded: bigint; paymentsSum: bigint; discrepancy: bigint; reconciled: boolean }.

Acceptance Criteria

• reconcilePayments(invoiceId: string): Promise<ReconciliationReport> exported
• reconciled: true when invoiceFunded === paymentsSum
• discrepancy is absolute difference between the two values
• ReconciliationReport type exported from src/index.ts
• Test verifies discrepancy detected when values differ
• All existing tests pass
• TypeScript strict mode — zero any types

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[Joseph-1-Duro]

@Joseph-1-Duro has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hey, I would love to work on your project

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[Arome8240]

@Arome8240 has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Can I work this issue?

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[Ademiitura]

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

Please can I work on this issue
Thanks

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[oraimoitel]

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

Can I work on this please 🙏🙏🙏, am an experienced full stack developer.

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[Onomebello]

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

Hello i would like to work on this issue

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[drips-wave]

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

🧑‍💻 @Onomebello: 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.

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