Add mock/stub for Stellar RPC client

[AbelOsaretin]

What

No reusable mock exists for the Stellar RPC client. Each test file would need to create its own mocks.

Why

A shared mock ensures consistent behavior across tests and reduces boilerplate.

Scope

• Create a mock Stellar RPC server class
• Implement getAccount, sendTransaction, getTransaction, simulateTransaction, prepareTransaction
• Support configurable responses and errors
• Export for use in all test files

Acceptance Criteria

• Mock class: MockRpcServer or similar
• Methods return configurable responses
• Methods throw configurable errors
• Easy to set up per-test scenarios

Technical Context

• src/lib/stellar.ts:15-18 — rpcServer singleton
• Methods used: getAccount, sendTransaction, getTransaction, simulateTransaction, prepareTransaction
• Could use jest.mock() or a manual mock class

[OmniZlatoon]

@OmniZlatoon has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

What can I do for you to assign me this issue sir? I assure you completion of the issue on time with expected output.

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[jerryjuche]

@jerryjuche has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

i would love to work on this issue

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[OgbuKingsley166]

@OgbuKingsley166 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hello maintainer can I work on this?

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[webdevayo]

@webdevayo has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

I will love to work on this. please assign.

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[badmusdare4]

@badmusdare4 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hello maintainer, I have read through the issue and I’m sure I can provide a solution that meets the acceptance criteria.

Please consider assigning it to me.

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[LawalRahman]

@LawalRahman has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi! I'd love to contribute to this project. I have experience building and maintaining production applications and enjoy working on well-scoped tasks. I focus on writing clean, maintainable code, communicating clearly, and delivering quality work on time. I'm excited about the opportunity to contribute and collaborate with the team.

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[drips-wave]

Congratulations, @LawalRahman! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

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[drips-wave]

This issue has been completed by @LawalRahman as part of the Stellar Wave Program's 7th Wave 🥳

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