refactor: unify impl operation gates and correction verification

harness/tests/common/test_pytest_evidence_recipe.py

@@ -7,6 +7,7 @@ import importlib.util
 import json
 import os
 from pathlib import Path
+from harness.tests.common.impl_contract_docs import read_contract
 import subprocess
 import sys
 import tempfile
@@ -19,7 +20,7 @@ HEADING = '### Conditional pytest evidence recipe'
 
 class PytestEvidenceRecipeTests(unittest.TestCase):
     def recipe(self):
-        text = SKILL.read_text()
+        text = read_contract(SKILL)
         self.assertIn(HEADING, text, 'conditional pytest recipe is missing')
         section = text.split(HEADING, 1)[1].split('\n### ', 1)[0]
         return section, json.loads(section.split('```json\n', 1)[1].split('\n```', 1)[0])