Add test coverage that cancel_admin_transfer clears both the pending admin and the pending eta

[mikewheeleer]

Test that cancel_admin_transfer wipes the pending admin and its queued eta together

Description

cancel_admin_transfer in src/lib.rs removes both DataKey::PendingAdmin and DataKey::PendingAdminEta, and is documented as a no-op when nothing is pending. A botched cancel that cleared only one of the two slots would leave a dangling eta or a pending admin with no eta, breaking the timelock invariant. The existing suites cover propose/accept and the eta read, but there is no direct assertion that cancel clears both slots and is safely idempotent. This issue adds that coverage.

Requirements and context

• Repository scope: StableRoute-Org/Stableroute-contracts only.
• Test the full flow: set a timelock, propose a transfer (stamping pending admin + eta), then cancel and assert get_pending_admin() and get_pending_admin_eta() both return None.
• Test that calling cancel_admin_transfer with nothing pending is a no-op and does not panic.
• Test that a non-admin caller is rejected.
• Distinct from issues-4 "emit a cancelled event on cancel" (a feature) — this issue is pure cancel-state coverage.

Suggested execution

• Fork the repo and create a branch
• git checkout -b test/contracts-cancel-admin-transfer-coverage
• Implement changes
  • Write code in: src/lib.rs — no production change expected.
  • Write comprehensive tests in: src/lib.rs (inline #[cfg(test)] mod test) — cover the propose-then-cancel clearing of both slots, the no-pending no-op, and non-admin rejection.
  • Add documentation: none required beyond test doc comments.
  • Include NatSpec-style doc comments (///) on each new test, matching the existing style in lib.rs.
  • Validate security assumptions: no dangling eta, no orphan pending admin, admin-only cancel.
• Test and commit

Test and commit

• Run cargo fmt --all -- --check, cargo build, and cargo test.
• Cover edge cases: cancel after propose, cancel with nothing pending, and unauthorized cancel.
• Include the full cargo test output in the PR description.

Example commit message

test: cover cancel_admin_transfer clearing both pending admin and eta

Guidelines

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

Community & contribution rewards

• 💬 Join the StableRoute community on Discord for questions, reviews, and faster merges: https://discord.gg/37aCpusvx
• ⭐ 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.

[gloskull]

Hi, I’d love to work on this issue. I have 4 years of experience across backend, frontend, full-stack, and smart contract development. I understand the task clearly and can deliver a clean, efficient, well-tested solution on time, with strong focus on code quality and maintainability. My PR will be submitted in under 10 hours.