feat(deploy): add automated build and testnet deployment script

[godamongstmen897]

Closes #2

Description

This PR introduces an automated deployment and build script (deploy.sh) inside the contracts directory, alongside execution walkthrough documentation. The script streamlines the entire local smart contract pipeline—handling compilation, optimization, and target network broadcasting seamlessly.

Key Changes

• Automated Pipeline Script: Added contracts/deploy.sh to automate building the Rust smart contract via Cargo, optimizing the WebAssembly binary using the Soroban CLI, and handling deployment workflows.
• Walkthrough Documentation: Added contracts/walkthrough.md to document implementation parameters and step-by-step verification flows.

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Acceptance Criteria Verification

• Create a deploy.sh or a Makefile script: Implemented complete bash automation sequence.
• Compile and optimize using soroban contract optimize: The script successfully targets wasm32-unknown-unknown and outputs an optimized production .wasm footprint.
• Execute deployment to Stellar Testnet and print Contract ID: Completed successfully.
• Scope Control: Verified via git status that no files outside the contracts/ directory were modified or touched.

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Closes #2

Proof of Work (PoW)

📍 Testnet Contract ID

CDYCOYS5SXK4F43I2DZ4NN7END2V55JGZ73MU7SGRH2EUFJHHHSLNQPK

[Queenode]

Thank you so much for contributing to Kolo.
Great work Dev