Phase 3 verification: - All 13 core modules pass syntax check - 217 type annotations applied across gui_2.py and gui_legacy.py (zero remaining) - python.md styleguide updated to AI-optimized standard - BOM markers on 3 files are pre-existing (Phase 2), not regressions Track: python_style_refactor_20260227 — ALL PHASES COMPLETE Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>