Build LP position indexing and rewards API endpoints

[Chucks1093]

Summary

Index liquidity provider events from the contract and expose endpoints for fetching LP positions, accrued rewards, and pool share data per wallet.

Scope

• GET /lp/positions?wallet= — all active LP positions with share and accrued rewards
• GET /lp/positions/:lpId — single position detail
• GET /lp/pool/:keyId — total pool size and current APR estimate
• LP events (added, claimed, removed) indexed from contract stream
• Rewards accrual computed on each trade event

Acceptance Criteria

• Positions list returns correct share percentage and rewards per wallet
• Pool endpoint returns accurate total size and APR
• Events indexed without gaps from contract stream
• Rewards accrual computed correctly on each trade
• Unauthorized requests return 401

ETA

12 hours

[aduagba4133]

@aduagba4133 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Hello, I’ve gone through the requirements and I’m confident I can implement a proper solution that matches the acceptance criteria. Kindly assign this issue to me.

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[Depo-dev]

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Can i work on this?

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[flare-999]

@flare-999 has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

I'm interested in working on this
maintainer, assign this issue to me

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[Jessicaayegh]

@Jessicaayegh has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Please assign to me

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

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This issue has been completed by @Depo-dev as part of the Stellar Wave Program's 9th Wave 🥳

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