- Replaced global timer mocks with local `YieldGate` instances to avoid test flakiness from concurrent environment interference.
- Introduced an injected clock and counting sleep pattern to test gating logic without relying on `process` globals.
- Added a test case to ensure the gate correctly handles negative clock jumps without stalling.
- Replaced Bun.sleep with scheduler.wait for Node-compatible cancellable sleeps.
- Added module-level timestamp gate to skip yields within 50ms of the last one.
- Threaded AbortSignal through ExponentialYield.sleep to cancel losing timers in race.
- Added tests covering gate behaviour and stray-timer cancellation.