fix(rectification): close round A/2 tail gaps in tests, CI, and stale-score reuse

Window_scan assertions now match the public from_sign/to_sign contract, the
staging quick gate runs the rectification Python suite, and compare-candidates
rescores when stored policy lags the live engine identity.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/test_rectification_v5_services.py

@@ -675,11 +675,26 @@ class RectificationV5ServicesTest(unittest.TestCase):
             "rectification-v5-candidate-features": "/api/rectification/v5/candidate-features",
             "rectification-v5-score": "/api/rectification/v5/score",
             "rectification-v5-diagnostics": "/api/rectification/v5/diagnostics",
+            "rectification-v5-versions": "/api/rectification/v5/versions",
         }
         for command, endpoint in expected.items():
             self.assertEqual(API_COMMAND_MAP[command], endpoint)
             self.assertIn(endpoint, TECHNIQUE_EXAMPLE_ENDPOINTS)
 
+    def test_engine_scoring_versions_match_score_identity(self):
+        from scripts.rectification.api_service import engine_scoring_versions
+        from scripts.rectification.decision_policy import POLICY_VERSION
+        from scripts.rectification.scoring_service import ALGORITHM_VERSION
+
+        versions = engine_scoring_versions()
+        self.assertEqual(versions["algorithm_version"], ALGORITHM_VERSION)
+        self.assertEqual(versions["decision_policy_version"], POLICY_VERSION)
+        handler = object.__new__(JyotishAPIHandler)
+        payload = handler._compute_rectification_v5_versions()
+        self.assertEqual(payload["algorithm_version"], ALGORITHM_VERSION)
+        self.assertEqual(payload["decision_policy_version"], POLICY_VERSION)
+        self.assertEqual(payload["endpoint"], "rectification_v5_versions")
+
     def test_zero_evidence_returns_declared_window_report(self):
         body = request(start_time="23:58", end_time="00:02")
         body["events"] = []