[CT-18] Write comprehensive tests for assetsup tokenization module in opsce crate

[yusuftomilola]

Problem

contracts/assetsup/src/tokenization.rs has minimal test coverage. Core functions like mint_tokens(), burn_tokens(), and transfer_tokens() are untested, meaning regressions in these critical financial operations go undetected.

Proposed Solution

Create contracts/opsce/src/tokenization_tests.rs as a dedicated test module using the Soroban SDK test environment (soroban_sdk::testutils).

Acceptance Criteria

• tokenize_asset() — success, re-tokenization of already-tokenized asset fails
• mint_tokens() — success, minting beyond max supply fails
• burn_tokens() — success, burning more than owned balance fails
• transfer_tokens() — success, transfer without sufficient balance fails, self-transfer is prevented
• get_token_balance() — returns correct balance after a series of mints and transfers
• All tests use soroban_sdk::testutils::Address::random for test addresses
• Tests run cleanly with cargo test -p assetsup

[ummarig]

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

Can I please be assigned this task

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

[drips-wave]

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

🧑‍💻 @ummarig: 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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