Normalize runtime events and tighten orchestration approval flow

- migrate fixtures/tests/adapters to canonical provider runtime event payloads
- route checkpoint capture off `turn.completed` only and drop legacy `checkpoint.captured` path
- stop faking approval resolution when provider reports stale/unknown pending requests
7c5a543fffJulius Marminge committed on 3/6/2026, 2:13:19 AMparent196f331
20 files changedLine totals unavailable