Implement multi-signature Soroban contract execution workflow

[Just-Bamford]

Description

Problem

Contract execution workflows currently assume a single signing path. Applications requiring N-of-M authorization must manually coordinate signature collection and construct the final transaction.

This makes multi-party contract execution difficult to implement consistently.

Solution

Implement a contract execution workflow that separates transaction preparation, signing-request creation, signature collection, validation, and final submission.

The workflow should support configurable signer thresholds and prevent execution until the required valid signatures have been collected.

Acceptance Criteria

• Multi-signature contract execution infrastructure is implemented.
• N-of-M signer configuration is supported.
• Signing requests contain a canonical transaction payload.
• Signatures are validated before being accepted.
• Duplicate signer submissions are rejected.
• Signature collection status is queryable.
• Execution is blocked until the threshold is satisfied.
• Invalid signatures do not count toward the threshold.
• Expired signing requests cannot be executed.
• Tests cover threshold satisfaction, invalid signatures, duplicate signatures, expiration, and execution.
• Exported through src/soroban/index.ts and src/index.ts.

Note for Contributors

Reuse existing transaction signing and verification utilities. Do not introduce an independent signing format unless there is a documented protocol requirement.

[Mayor-Isaac]

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

Hi Maintainer! I’m interested in contributing to this task and can work toward delivering a clean solution on time.

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[paulddeveloper-droid]

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

I’d like to work on this issue. I’ve reviewed the requirements and understand the expected changes. I’ll follow the existing project patterns, add the required tests, and keep the implementation within the stated scope. I’m ready to start.

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[obedojukwu16-jpg]

@obedojukwu16-jpg has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I will like to work on this project, I know exactly what to do and I will deliver efficiently.

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[Yasir-TechGuy]

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

Hi maintainer I will like to work on this issue, I can fix it and deliver a clean pr asap

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[emarkees]

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

Hello, I can help you fix this issue, Kindly assign

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[Johnalex-hub]

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

Good day team. My name is John and i am a fullstack web3 developer. I have gone through the scope of the issue and i can guarantee my ability in getting this done. Can i please get assigned

ETA :48 hrs

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

[drips-wave]

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

🧑‍💻 @Johnalex-hub: 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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