Implement dividend pool distribution API endpoints

[Chucks1093]

Summary

Build REST endpoints for fetching dividend distribution history per key, per-holder pending dividends, and submitting claim transactions to the Soroban contract.

Scope

• GET /keys/:keyId/dividends — distribution history with pagination
• GET /holders/:wallet/dividends — aggregate pending and claimed across all held keys
• POST /keys/:keyId/dividends/claim — build and return unsigned claim transaction
• Dividend data indexed from contract events
• Cache distribution history with 60s TTL

Acceptance Criteria

• Distribution history returns paginated events with correct amounts
• Holder aggregate returns correct pending and claimed totals per key
• Claim endpoint returns valid unsigned transaction
• Events indexed correctly from contract logs
• Cache invalidated after claim transaction confirmed

ETA

12 hours

[guptakumarranjeet150]

Hey team,

I would like to resolve this issue. Here is my proposed execution plan:

• Implementation: Build out the handlers for Implement dividend pool distribution API endpoints ensuring proper HTTP status codes and error propagation.
• Testing: Add integration test suites for standard invocations and boundary/error conditions.

Looking forward to collaborating on this—please assign!

[T-kesh]

@T-kesh has applied to work on this issue as part of the Stellar Wave Program's 9th wave.

Please assign me

ℹ️ Repo Maintainers: To accept this application, review their application or assign @T-kesh to this issue.

[Justkoredx]

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

Hi! I’ve looked through the issue and believe I can resolve it effectively. Kindly assign it to me.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Justkoredx to this issue.

[Gojv-byte]

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

Hello maintainer please assign me this issue and expect fast PR

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Gojv-byte to this issue.

[chidii]

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

Hello Maintainer, I've reviewed this issue thoroughly and I'm well positioned to resolve it — experienced across the relevant stack and comfortable navigating the existing codebase. Ready to start right away.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @chidii to this issue.

[JerryOJJ]

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

I would like to work in this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @JerryOJJ to this issue.

[drips-wave]

Congratulations, @T-kesh! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on September 30, 2026.

🧑‍💻 @T-kesh: 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.

Warning

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