fix: remove ineffective mutation validation

scripts/run_task.py

@@ -11,7 +11,6 @@ if str(ROOT_DIR) not in sys.path:
 
 from engine.artifact_manager import ArtifactManager
 from engine.decision_engine import decide_candidate
-from engine.mutation_engine import MutationValidationError, validate_candidate_changes
 from engine.runner import run_command
 from engine.scorer import parse_score_output
 from engine.task_loader import load_task
@@ -59,19 +58,6 @@ def main() -> int:
     artifact_manager = ArtifactManager(task)
     snapshot = artifact_manager.snapshot()
 
-    try:
-        validate_candidate_changes(task, snapshot)
-    except MutationValidationError as exc:
-        return _emit_record(
-            repo_root=repo_root,
-            task_id=task.id,
-            results_file=task.logging.results_file,
-            status="discard",
-            reason=str(exc),
-            candidate_score=None,
-            diff_summary=artifact_manager.diff_summary(snapshot),
-        )
-
     run_result = run_command(
         task.runner.command,
         _resolve_repo_path(repo_root, task.runner.cwd),