refactor: unify impl operation gates and correction verification

harness/tests/common/test_delegation_evidence_contract_docs.py

@@ -1,5 +1,6 @@
 """Procedural consumer wiring is not proof of live agent execution."""
 from pathlib import Path
+from harness.tests.common.impl_contract_docs import read_contract
 import unittest
 
 ROOT = Path(__file__).resolve().parents[2]
@@ -15,7 +16,7 @@ class DelegationEvidenceContractTests(unittest.TestCase):
     def test_consumers_require_gate_before_adoption(self):
         for path in ROLES:
             with self.subTest(path=path):
-                text = (ROOT / path).read_text()
+                text = read_contract(ROOT / path)
                 for required in ['## Delegation evidence acceptance gate',
                                  'delegation_evidence.py', '위임 결과 채택 이전',
                                  'main이 독립적으로 고정한 context',