feat: add BLIF Flow v2 authoritative operational adapter

tests/test_opportunity_next_action_bulk.py

@@ -8,6 +8,12 @@ import app.opportunity_next_action_service as service
 from app.domain.opportunity_flow import build_opportunity_evidence
 
 
+@pytest.fixture(autouse=True)
+def _v1_contract_mode(monkeypatch):
+    """These tests measure the legacy bulk contract, independently of env mode."""
+    monkeypatch.setattr(service.settings, "blif_flow_v2_mode", "off")
+
+
 class _Result:
     def __init__(self, rows):
         self._rows = rows