Add integration test for trade indexer correctly persisting buy events from Soroban transaction stream

[Chucks1093]

Summary

The trade indexer processes buy events from the Soroban transaction stream and writes them to the database, but there is no integration test confirming the persisted record matches the on-chain event fields. A test should simulate an incoming buy event and assert the database record is correct.

Scope

• Feed a mock Soroban buy event into the indexer pipeline
• Assert a trade record is created in the database with matching: buyer, creator_id, quantity, price, ledger, timestamp
• Assert no duplicate record is created if the same event is processed twice (idempotency)
• Assert an event with a missing required field is skipped and logged

Acceptance Criteria

• Trade record created with all six fields correct
• Duplicate event does not create a second record
• Malformed event skipped without crashing the indexer
• Skipped event produces a warn-level log

ETA: 12 hours

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Coordinate on Telegram

[Waffiyyi]

@Waffiyyi has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I would love to work on this issue. Please assign this to me.

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[Bilalishaq7]

@Bilalishaq7 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

gooday maintainer, i can fix this and i'd submit a PR shortly after assignment

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[AbuJulaybeeb]

@AbuJulaybeeb has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi Maintainer, haven reviewed the description of the issue, and well experienced with Js Library,
I would like to hop on the issue and sure to deliver at ETA 2hrs

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[Mosas2000]

@Mosas2000 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi maintainer, will appreciate you letting me work on this.

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Congratulations, @Mosas2000! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

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[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Official Campaign | FWC26 campaign!

@Mosas2000's PR #639 was approved and merged by @Chucks1093.

🏆 @Mosas2000: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (887 total points). Track your full progress on GrantFox.

👏 Great work, @Mosas2000! Keep contributing to accesslayerorg.

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This issue has been completed by @Mosas2000 as part of the Stellar Wave Program's 7th Wave 🥳

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