Select phase-specific working context and retain auditable source evidence

tests/test_hypothesis_builder.py

@@ -94,7 +94,7 @@ def test_generation_budget_registry_and_preservation(interpreted_case):
             if name != "manifest.json": assert before.read_bytes(name) == after.read_bytes(name)
     assert original.read_bytes() == original_bytes
     assert len(adapter.requests) == 1
-    assert adapter.requests[0]["prompt_version"] == "hypotheses_v3"
+    assert adapter.requests[0]["prompt_version"] == "hypotheses_v4"
     assert case_builder.build("case-A","stable-package").reused
     assert asyncio.run(CaseInterpreter(store,gateway(adapter)).interpret("case-A","stable-package")).reused