- api.parse_837 / parse_835: pass request.app.state.event_bus into store.add()
- conftest: autouse fixture wires a fresh EventBus onto app.state for every
test, since TestClient does not invoke the FastAPI lifespan handler
unless used as a context manager
- test_pubsub: split get_event_bus coverage into a raises-when-missing test
and a returns-attached-bus test, both save/restore app.state.event_bus
around the assertion so the autouse fixture's bus is preserved
Phase 2 complete: db init moved to lifespan, EventBus is the process-wide
publish point, and the two ingest endpoints publish claim_written /
remittance_written / activity_recorded events on every store.add().
Tyler