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>

scripts/mcp_server.py

@@ -78,7 +78,7 @@ async def call_tool(name: str, arguments: dict) -> list[TextContent]:
         return [TextContent(type="text", text=f"ERROR: {e}")]
 
 
-async def main():
+async def main() -> None:
     async with stdio_server() as (read_stream, write_stream):
         await server.run(
             read_stream,