- Add `pytestmark = pytest.mark.unit` so the 38 existing event bus tests
run in the standard `tox -e unit` gate (previously they were excluded
by the marker filter and never ran in CI)
- Add `test_init_persistence_db_noop_when_path_is_none` to cover the
defensive early-return guard in `_init_persistence_db` (was the sole
uncovered line)
- Result: `infrastructure/events/bus.py` at 100% coverage; unit suite
grows from 474 → 513 tests
Fixes#917
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
