[CT-08] Add insurance tracking to shipment contract

[mftee]

Problem

Whether a shipment is insured is tracked only in the PostgreSQL database. The Soroban blockchain has no record of insurance status, so on-chain escrow dispute and refund decisions cannot reference insurance — the two systems are completely decoupled with no shared truth.

Proposed Solution

Add insurance metadata to a new shipment contract inside contracts/package/shipment-insurance/ so that insurance status is provably recorded on-chain and accessible to other contracts.

Note: All work must be done inside the contracts/package/ directory. Do not modify any existing contract files outside this folder.

Acceptance Criteria

• create_shipment accepts is_insured: bool, insurance_premium: i128, and insurance_policy_id: String
• get_insurance_status(shipment_id) returns { is_insured, premium, policy_id }
• When a dispute is opened on an insured shipment, the contract emits an InsuranceClaim event with the policy ID
• Uninsured shipments store is_insured: false and zero values for premium and policy ID
• insurance_policy_id maximum length is 64 characters; longer values return PolicyIdTooLong error
• Unit tests cover: insured shipment creation, uninsured shipment creation, dispute event on insured shipment

[Nuel-ship-it]

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

Hi 👋, I'm emma, a frontend engineer and Solidity developer currently learning backend development with Rust. I also have experience working with Starknet and Cairo, alongside Node.js, TypeScript, and PostgreSQL.

I’d love to work on this issue and I’m confident I can implement it cleanly while contributing effectively to the project. Looking forward to contributing 🚀

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Nuel-ship-it to this issue.

[A6dulmalik]

@A6dulmalik has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I’m interested in implementing the shipment insurance contract with on-chain insurance metadata, dispute event handling, and strict policy ID validation.
I can deliver the full contract and unit tests for insured/uninsured flows and InsuranceClaim event emission entirely within the contracts/package/ scope.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @A6dulmalik to this issue.

[drips-wave]

Congratulations, @A6dulmalik! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @A6dulmalik: 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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