[BE-64] Implement Stellar lease, insurance, and KYC management API

[yusuftomilola]

Overview

The assetsup contract and contrib contract support lease agreements, insurance policies on assets, and KYC verification for investors. This issue exposes these modules. Enables FE-47 (Lease UI), FE-48 (Insurance UI), and FE-50 (KYC UI).

Context

• Contract sources: contracts/assetsup/src/lease.rs, contracts/assetsup/src/insurance.rs, contracts/contrib/src/ (KYC module)
• Depends on BE-60 (StellarService)
• KYC is required before a user can acquire tokens in a tokenized asset

Acceptance Criteria

• POST /stellar/assets/:id/lease body: { lesseeAddress, startDate, endDate, monthlyRent, deposit } — records lease agreement on-chain via contracts/assetsup/src/lease.rs
• GET /stellar/assets/:id/lease — retrieves current or historical lease terms from on-chain storage
• PATCH /stellar/assets/:id/lease/terminate — terminates the active lease on-chain
• POST /stellar/assets/:id/insurance body: { insurer, policyNumber, coverage, premium, startDate, endDate } — records insurance policy on-chain
• GET /stellar/assets/:id/insurance — retrieves insurance details
• POST /stellar/kyc/submit body: { documentType, documentNumber, country, expiryDate } — submits KYC data to the contrib contract's KYC module for review
• GET /stellar/kyc/status — returns current user's KYC status: PENDING, VERIFIED, REJECTED

[adeboladee]

@adeboladee has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hello maintainer, Please I would like to work on this issue

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

[Lazaruster]

@Lazaruster has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

i will love to work on this issue

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

[Nimatstar]

@Nimatstar has applied to work on this issue as part of the Stellar Wave Program's 6th wave.

Hi can i work on this task?

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

[drips-wave]

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

🧑‍💻 @Nimatstar: 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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