Build cross-chain reference tracker

[Kingsman-99]

Labels: complexity: high

Add getCrossChainRef(invoiceId) that fetches the cross_chain_ref field for an invoice and parses it into a structured format. Also add setCrossChainRef for creators to attach a cross-chain reference at creation time.

Acceptance criteria:

• getCrossChainRef(invoiceId) returns { ref: string | null }
• parseChainRef(ref) returns { chain, txHash, blockNumber } when ref matches known formats
• Exported with TypeScript types
• Included in getInvoice response automatically

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[egwujiohaifesinachiperpetual-max]

@egwujiohaifesinachiperpetual-max has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

plrase assign to me

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[augustinemartins]

@augustinemartins has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi, can I get to work on this?

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[Menjay7]

@Menjay7 has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi! I’m a full-stack developer with a strong blockchain background. I’d love to handle this issue and can deliver a clean, reliable solution. Kindly assign it to me.

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Congratulations, @augustinemartins! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 30, 2026.

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