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>

tests/test_hooks.py

@@ -11,12 +11,12 @@ sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), "..")))
 from api_hook_client import ApiHookClient
 import gui_legacy
 
-def test_hooks_enabled_via_cli():
+def test_hooks_enabled_via_cli() -> None:
  with patch.object(sys, 'argv', ['gui_legacy.py', '--enable-test-hooks']):
   app = gui_legacy.App()
   assert app.test_hooks_enabled is True
 
-def test_hooks_disabled_by_default():
+def test_hooks_disabled_by_default() -> None:
  with patch.object(sys, 'argv', ['gui_legacy.py']):
   if 'SLOP_TEST_HOOKS' in os.environ:
    del os.environ['SLOP_TEST_HOOKS']