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/verify_mma_gui_robust.py

@@ -33,12 +33,12 @@ class TestMMAGUIRobust(unittest.TestCase):
   print("GUI started.")
 
  @classmethod
- def tearDownClass(cls):
+ def tearDownClass(cls) -> None:
   if cls.gui_process:
    cls.gui_process.terminate()
    cls.gui_process.wait(timeout=5)
 
- def test_mma_state_ingestion(self):
+ def test_mma_state_ingestion(self) -> None:
   """Verify that mma_state_update event correctly updates GUI state."""
   track_data = {
    "id": "robust_test_track",
@@ -69,7 +69,7 @@ class TestMMAGUIRobust(unittest.TestCase):
   self.assertEqual(status["active_tickets"][2]["status"], "complete")
   print("MMA state ingestion verified successfully.")
 
- def test_mma_step_approval_trigger(self):
+ def test_mma_step_approval_trigger(self) -> None:
   """Verify that mma_step_approval event sets the pending approval flag."""
   payload = {
    "ticket_id": "T2",