docs: Add API documentation for service layer

[Akatenvictor]

No documentation for API endpoints, request/response shapes.

Acceptance Criteria: Document all service endpoints

[oladeeayo]

@oladeeayo has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi, I would love to jump on this issue

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[investorUsman]

@investorUsman has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi maintainers! I’d love to take on this issue. I’m eager to make my first contribution to this wave, and I have the time and consistency to get this fixed right away. Please assign it to me, and I’ll have a PR ready for review shortly!

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[RohithPariki]

@RohithPariki has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I would love to work on this issue because clear API contract documentation is critical for system integration and developer velocity. I have extensive experience mapping service layers and documenting REST/GraphQL endpoints, including precise request payloads, response shapes, status codes, and authentication requirements. I am comfortable auditing your codebase to extract these details and writing clean, structured API references that match your project standards and fulfill all acceptance criteria.

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[devpeter999]

@devpeter999 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi Maintainer! I’d love to take on this issue and contribute a solid solution.
I’ve reviewed the requirements and I’m confident I can implement the fix effectively.
I’m happy to get started and keep the changes clean, tested, and well-documented.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @devpeter999 to this issue.

[drips-wave]

Congratulations, @devpeter999! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

🧑‍💻 @devpeter999: 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.

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[drips-wave]

This issue has been completed by @devpeter999 as part of the Stellar Wave Program's 8th Wave 🥳

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