[CT-32] Add revenue distribution query functions

[yusuftomilola]

Overview

Add read-only query functions for the revenue_distribution contract. Work inside contracts/sandbox/revenue_distribution/.

Acceptance Criteria

• get_beneficiaries(env) -> Vec<Beneficiary> returns current beneficiary list
• get_distribution(env, id) -> Result<Distribution, Error> returns distribution record
• get_all_distributions(env) -> Vec<String> returns all distribution IDs
• has_claimed(env, distribution_id, beneficiary) -> bool
• get_contract_balance(env) -> u128 returns current token balance held by the contract
• Code compiles with cargo build

[nottherealalanturing]

@nottherealalanturing has applied to work on this issue as part of the Stellar Wave Program's 4th wave.

Hi, I’d like to work on this issue.

I’m a software engineer with strong experience in JavaScript and building scalable web applications. I’m comfortable working across the stack, writing clean, maintainable code, and collaborating in open source environments.

I’ve reviewed the issue and I’m confident I can implement a solid solution while following the project’s conventions.

Please assign this issue to me, I'd be happy to contribute.

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

[drips-wave]

Congratulations, @nottherealalanturing! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on April 29, 2026.

🧑‍💻 @nottherealalanturing: 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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[drips-wave]

This issue has been completed by @nottherealalanturing as part of the Stellar Wave Program's 4th Wave 🥳

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