Oracle: formalize randomness provider interface

[Otaiki1]

Build location

Work primarily in oracle/src/randomness. Keep related tests/docs beside that package unless this issue explicitly calls for a cross-package update.

Why this matters

The oracle should expose one interface for VRF, PRNG fallback, and future randomness providers.

What to build

• Define provider interface for request validation, seed generation, proof generation, and verification metadata.
• Adapt existing VRF/PRNG services to the interface.
• Record provider type per randomness response.

Acceptance criteria

• Tests cover provider selection and failure paths.
• Submitter receives a provider-agnostic randomness result.

Suggested verification

cd oracle && npm run lint && npm run test && npm run build

[Zarmaijemimah]

@Zarmaijemimah has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I’ll love to work on this issue please kindly assign thank you.

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[Emelie-Dev]

@Emelie-Dev has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi, I would love to work on this issue.

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

[drips-wave]

Congratulations, @Zarmaijemimah! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

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