[BE-030] Create toggle API endpoint for auto-earn preferences

[ONEONUORA]

Description

Create POST /api/yield/toggle-auto allowing users to activate or deactivate the automatic sweep of idle funds.

Files to Edit/Create

• backend/src/api/yield.rs

Acceptance Criteria

• Save preference state (boolean) in user's profile table.

Guidance / Hints

Return status confirmation payload showing auto-earn state.

[alexitsejames-cpu]

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

Hi can you please assign these issue to me

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[ositaemmanuel653-netizen]

@ositaemmanuel653-netizen has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

I have a solid understanding of the underlying architecture required for this task and am ready to start testing a solution immediately.

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[aliyuHabibu]

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

Hi, I'm a software engineer. I have gone through the issue and I can resolve it, assign it to me. Thank you

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[josephchimebuka]

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

Hi GM, I have reviewed this issue and taken the time to understand the requirements, current implementation, and the expected outcome. Based on my analysis, I believe this is something I can successfully handle and contribute to... Kindly assign

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[josephchimebuka]

Implemented in #426 — will close this issue when merged.

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This issue has been completed by @josephchimebuka as part of the Stellar Wave Program's 6th Wave 🥳

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