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_performance_monitor.py

@@ -8,7 +8,7 @@ sys.path.append(os.path.abspath(os.path.join(os.path.dirname(__file__), "..")))
 
 from performance_monitor import PerformanceMonitor
 
-def test_perf_monitor_basic_timing():
+def test_perf_monitor_basic_timing() -> None:
  pm = PerformanceMonitor()
  pm.start_frame()
  time.sleep(0.02) # 20ms
@@ -17,7 +17,7 @@ def test_perf_monitor_basic_timing():
  assert metrics['last_frame_time_ms'] >= 20.0
  pm.stop()
 
-def test_perf_monitor_component_timing():
+def test_perf_monitor_component_timing() -> None:
  pm = PerformanceMonitor()
  pm.start_component("test_comp")
  time.sleep(0.01)