[CT-41] Add Makefile and deploy script for all sandbox contracts

[yusuftomilola]

Overview

Write a Makefile and shell script to build and deploy all sandbox Soroban contracts to the Stellar testnet in one command. This makes it easier for contributors to test contract interactions end to end.

Acceptance Criteria

• contracts/sandbox/Makefile with targets: build-all, test-all, deploy-all
• build-all runs cargo build --target wasm32-unknown-unknown --release for every sandbox contract
• test-all runs cargo test for every sandbox contract
• deploy-all reads STELLAR_SECRET_KEY and STELLAR_NETWORK from environment variables
• Each deployed contract ID is written to a deployed-ids.env file
• Script prints a summary table of all deployed contract IDs
• A contracts/sandbox/README.md section explains how to run each target
• All targets succeed on a clean checkout with the Stellar CLI installed

[rmsb-art]

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

Hello, I’d like to be assigned to this. I bring senior-level experience in TypeScript and will prioritize clean abstractions, solid test coverage, and clear communication throughout the process.

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

[drips-wave]

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

🧑‍💻 @rmsb-art: 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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🌊 Happy Wave 🌊

[drips-wave]

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

😎 @rmsb-art: You earned 200 Points for completing this issue! After the current Wave ends, you'll be eligible for a percentage of the Wave's reward pool based on the percentage of total points you've earned. Learn more here. You can also Leave a review to share your experience working on this issue.

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