refactor(types): auto -> None sweep across entire codebase

Applied 236 return type annotations to functions with no return values
across 100+ files (core modules, tests, scripts, simulations).
Added Phase 4 to python_style_refactor track for remaining 597 items
(untyped params, vars, and functions with return values).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

run_tests.py

@@ -45,7 +45,7 @@ def get_test_files(manifest: Dict[str, Any], category: str) -> List[str]:
  print(f"DEBUG: Found test files for category '{category}': {files}", file=sys.stderr)
  return files
 
-def main():
+def main() -> None:
  parser = argparse.ArgumentParser(
   description="Run tests with optional manifest and category filtering, passing additional pytest arguments.",
   formatter_class=argparse.RawDescriptionHelpFormatter,