refactor: unify impl operation gates and correction verification

harness/tests/common/test_inventory_binding_contract_docs.py

@@ -1,6 +1,7 @@
 """Contract wiring for the read-only inventory source-binding preflight."""
 import unittest
 from pathlib import Path
+from harness.tests.common.impl_contract_docs import read_contract
 
 ROOT = Path(__file__).resolve().parents[2]
 
@@ -15,7 +16,7 @@ class InventoryBindingDocumentationTests(unittest.TestCase):
         ]
         for path in paths:
             with self.subTest(path=path):
-                text = (ROOT / path).read_text()
+                text = read_contract(ROOT / path)
                 self.assertIn('test_inventory_binding.py', text)
                 self.assertIn('check-tests 이전', text)
                 self.assertIn('독립적으로 고정한 revision과 stage', text)