Summary
- Use unique per-fixture window IDs instead of millisecond timestamps, so Bun reruns cannot inherit a retained manager handle from an earlier fake DOM.
- Freeze the test clock so accidental reintroduction of timestamp IDs fails deterministically.
- Add a reproducible 100-rerun randomized routing soak command and run it in SDK CI.
Closes #269. This is a test-isolation fix; no production window lifetime semantics change.
Validation
- Before: 1,369 passes / 31 failures in the reported 1,400-test soak.
- After: 1,400 passes / zero failures / 3,300 assertions with the clock held fixed.
- Typechecks and focused Pickier pass.