Add tests for strict service-registration and service-disabled gates

[mikewheeleer]

Test the service-registration and service-disabled rejection paths

Description

The RequireServiceRegistration gate (ServiceNotRegistered #7) and the ServiceDisabled gate (#12) in record_usage in contracts/escrow/src/lib.rs are uncovered by contracts/escrow/src/test.rs. Neither register_service/unregister_service nor set_service_disabled is exercised against record_usage. This issue adds the missing coverage.

Requirements and context

• Repository scope: Agentpay-Org/Agentpay-contracts only.
• Cover: strict mode off allows unknown services; strict on + unregistered → panic #7; register then succeed; unregister then reject again.
• Cover: registered + disabled service → panic #12; re-enable then succeed; verify registration/metadata survive a disable.
• Assert is_service_registration_required, is_service_registered, and is_service_disabled round-trips.
• Test-only change unless a genuine bug surfaces.

Suggested execution

• Fork the repo and create a branch
• git checkout -b test/contracts-18-registry-gate-tests
• Implement changes
  • Write code in: contracts/escrow/src/lib.rs — no changes expected.
  • Write comprehensive tests in: contracts/escrow/src/test.rs — the registry/disabled scenarios above.
  • Add documentation: note covered behaviour in the test module header.
  • Include NatSpec-style doc comments (///) on any test helpers.
  • Validate security: disabled services cannot accrue usage.
• Test and commit

Test and commit

• Run cargo fmt --all -- --check, cargo build, and cargo test.
• Cover edge cases: disable an unregistered service, strict mode with disabled service, toggling order.
• Include the full cargo test output and a short security notes section in the PR description.

Example commit message

test: cover service-registration and service-disabled gates

Guidelines

• Minimum 95 percent test coverage for impacted modules.
• Clear, reviewer-focused documentation.
• Timeframe: 96 hours.

Community & contribution rewards

• 💬 Join the AgentPay community on Discord for questions, reviews, and faster merges: https://discord.gg/eXvRKkgcv
• ⭐ This is a GrantFox OSS / Official Campaign task and may be rewarded. When your PR is merged you'll be prompted to rate the project — if this issue and the maintainers helped you ship, we'd be grateful for a 5-star rating. Clear questions in Discord and tidy, well-tested PRs are the fastest path to a merge and a reward.

[1nonlypiece]

Hi Maintainers 👋,

I’d like to apply for this issue.

I have hands-on experience with Next.js frontend development as well as Stellar smart contracts using Rust (Soroban). I’m comfortable working with Figma designs, integrating APIs/wallets on the frontend, and implementing, testing, and optimizing smart contracts on Stellar.

I can follow the project guidelines, communicate progress clearly, and deliver clean, well-tested code within the expected timeline.

Looking forward to contributing to the project 🚀
Thanks!

[grantfox-oss]

🦊 GrantFox — @1nonlypiece has been assigned to this issue as part of the Official Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #18)
2. Your PR will be reviewed by the Agentpay-Org maintainers

Good luck! Track your progress on GrantFox.

[grantfox-oss]

🎉 This issue has been marked as completed on GrantFox as part of the Official Campaign campaign!

@1nonlypiece's PR #67 was approved and merged by @mikewheeleer.

🏆 @1nonlypiece: You earned 35 FoxPoints for this contribution! Your current tier: Explorer (328 total points). Track your full progress on GrantFox.

👏 Great work, @1nonlypiece! Keep contributing to Agentpay-Org.