test: final source recheck for V1 jet CV and V3 Taylor-Green runs

Both runners now re-derive the recorded source identity after the run
(source_provenance.final_source_check) and only then mark the receipt
complete. A changed source, or a recheck that fails, rewrites the receipt
as invalid and raises:
- V1: in-run receipts carry run_status=INCOMPLETE; finish_receipt sets
  COMPLETE or INVALID_SOURCE_CHANGED (+ source_recheck/source_after).
- V3: completed stays False, invalid=SOURCE_CHANGED_DURING_RUN, no
  screening_pass; the assessor requires source_recheck UNCHANGED (frozen
  mode still accepts receipts from before the field existed).
Interrupted runs keep INCOMPLETE / completed=False. Host tests cover
unchanged, changed and failed rechecks and incomplete runs. No threshold
or solver change.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/unit/test_jet_circle_cv.py

@@ -196,5 +196,40 @@ class Host(unittest.TestCase):
         self.assertTrue(record["src_sha256"])
 
 
+    def test_final_source_recheck_completes_or_invalidates_receipt(self):
+        import json
+        import tempfile
+        import run_jet_circle_cv as v
+        recorded = dict(source_mode="current_checkout", checkout_revision="a" * 40,
+                        checkout_dirty=False, src_tree="b" * 40)
+        payload = dict(status="PILOT_DIAGNOSTIC_ONLY", run_status="INCOMPLETE", windows=[1, 2])
+        with tempfile.TemporaryDirectory() as d:
+            path = Path(d) / "re100_s1.json"
+            path.write_text(json.dumps(payload))
+            done = v.finish_receipt(path, payload, recorded, lambda: dict(recorded))
+            self.assertEqual(json.loads(path.read_text()), done)
+            self.assertEqual((done["run_status"], done["source_recheck"]), ("COMPLETE", "UNCHANGED"))
+            for recheck, after in ((lambda: dict(recorded, checkout_dirty=True), True),
+                                   (lambda: v.verify(Path(d)), None)):
+                path.write_text(json.dumps(payload))
+                with self.assertRaisesRegex(RuntimeError, "Source changed during the run"):
+                    v.finish_receipt(path, payload, recorded, recheck)
+                bad = json.loads(path.read_text())
+                self.assertEqual((bad["run_status"], bad["source_recheck"]),
+                                 ("INVALID_SOURCE_CHANGED", "CHANGED"))
+                self.assertEqual(bad["source_after"] is None, after is None)
+                self.assertEqual(bad["windows"], [1, 2])
+            self.assertFalse(Path(str(path) + ".tmp").exists())
+
+    def test_receipts_written_during_the_run_are_incomplete(self):
+        """Static check (run_case needs CUDA): the in-run payload is INCOMPLETE and only
+        main() -> finish_receipt can mark it COMPLETE."""
+        import inspect
+        import run_jet_circle_cv as v
+        self.assertIn('run_status="INCOMPLETE"', inspect.getsource(v.run_case))
+        self.assertNotIn("COMPLETE\"", inspect.getsource(v.run_case).replace("INCOMPLETE\"", ""))
+        self.assertIn("finish_receipt(", inspect.getsource(v.main))
+
+
 if __name__ == "__main__":
     unittest.main()

tests/unit/test_validation_source_provenance.py

@@ -111,3 +111,20 @@ def test_historical_files_reports_unreadable_blob_as_history_unavailable(tmp_pat
         with pytest.raises(HistoryUnavailable, match="blob not in this clone"):
             source_provenance.historical_files(ROOT, ORIGIN, ["src/a.py"], tmp_path)
     assert not (tmp_path / "src/a.py").exists()
+
+
+def test_final_source_check_unchanged_changed_and_failed_recheck():
+    from source_provenance import final_source_check
+
+    recorded = dict(revision="a" * 40, dirty=False)
+    assert final_source_check(recorded, lambda: dict(recorded)) == dict(source_recheck="UNCHANGED")
+    changed = final_source_check(recorded, lambda: dict(recorded, dirty=True))
+    assert changed == dict(source_recheck="CHANGED", source_after=dict(recorded, dirty=True),
+                           source_recheck_error=None)
+
+    def fails():
+        raise RuntimeError("Source hash mismatch: src/x.py")
+
+    failed = final_source_check(recorded, fails)
+    assert (failed["source_recheck"], failed["source_after"]) == ("CHANGED", None)
+    assert "Source hash mismatch" in failed["source_recheck_error"]