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>

simulation/sim_ai_settings.py

@@ -4,7 +4,7 @@ import time
 from simulation.sim_base import BaseSimulation, run_sim
 
 class AISettingsSimulation(BaseSimulation):
- def run(self):
+ def run(self) -> None:
   print("\n--- Running AI Settings Simulation (Gemini Only) ---")
   # 1. Verify initial model
   provider = self.client.get_value("current_provider")