[BE] Support for Sending Raw XDR in Verification

[emdevelopa]

Context

In some advanced cases, a merchant might have the transaction XDR and want to verify it against a specific payment intent before it's even hit a block explorer (using pre-verification).

What 'Done' Looks Like

• POST /api/verify-payment/:id accepts an optional { xdr: '...' }.
• Validates that the XDR contains a payment matching the record requirements.

Complexity

Medium (150 points)

[WISDOM-WOKE22]

@WISDOM-WOKE22 has applied to work on this issue as part of the Stellar Wave Program's 3rd wave.

working on this

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Congratulations, @WISDOM-WOKE22! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on March 30, 2026.

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Warning

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This issue has been completed by @WISDOM-WOKE22 as part of the Stellar Wave Program's 3rd Wave 🥳

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