fix(rectification): separate adjacent minutes with transition proximity

Day-level events now score Vimshottari/Narayana transition closeness so
nearby candidate minutes can diverge, with gated quality probes and
answer-prior ranking so high-base-rate existence questions stay out.

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

tests/test_rectification_v5_services.py

@@ -488,7 +488,7 @@ class RectificationV5ServicesTest(unittest.TestCase):
         self.assertNotEqual(receipt["gates"]["exact_confirmation"]["external_validation_status"], "fail")
 
         self.assertEqual(first["decision_receipt"], receipt)
-        self.assertEqual(first["decision_policy_version"], "rectification-candidate-policy-v2")
+        self.assertEqual(first["decision_policy_version"], "rectification-candidate-policy-v3")
         self.assertTrue(receipt["display_allowed"])
         self.assertTrue(receipt["accept_allowed"])
         self.assertFalse(receipt["confirm_allowed"])