fix(pathfinder): satisfy pre-commit for spawned runner utilities

Add the missing type annotations required by mypy and keep the test shim exporting only the runner entry point so lint checks pass cleanly.

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

Author: cpcloud

cuda_pathfinder/cuda/pathfinder/_utils/spawned_process_runner.py

@@ -24,13 +24,19 @@ class CompletedProcess:
 
 
 class ChildProcessWrapper:
-    def __init__(self, result_queue, target, args, kwargs):
+    def __init__(
+        self,
+        result_queue: Any,
+        target: Callable[..., None],
+        args: Sequence[Any] | None,
+        kwargs: dict[str, Any] | None,
+    ) -> None:
         self.target = target
         self.args = () if args is None else args
         self.kwargs = {} if kwargs is None else kwargs
         self.result_queue = result_queue
 
-    def __call__(self):
+    def __call__(self) -> None:
         # Capture stdout/stderr
         old_stdout = sys.stdout
         old_stderr = sys.stderr

cuda_pathfinder/tests/spawned_process_runner.py

@@ -1,9 +1,6 @@
 # SPDX-FileCopyrightText: Copyright (c) 2025-2026 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 # SPDX-License-Identifier: Apache-2.0
 
-from cuda.pathfinder._utils.spawned_process_runner import (
-    PROCESS_KILLED,
-    PROCESS_NO_RESULT,
-    CompletedProcess,
-    run_in_spawned_child_process,
-)
+from cuda.pathfinder._utils.spawned_process_runner import run_in_spawned_child_process
+
+__all__ = ["run_in_spawned_child_process"]