Time display on InsertOverlay (CanvasLayer 10) shows station local time (HH:MM), day phase with cycle-tinted color, and day number. Reads SimulationTime from GameState.game_time via update_from_state(). Adds Constants.format_game_time() helper for testability. Placeholder layout — position refines when #314 wireframe lands. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>