Brainstormed design for backlog #6/#7: shell loop above the game loop,
GameIO.choose() primitive (console default + Swing buttons), GameSession
bundling savable state, JSON SaveData delta over the YAML world, single
active slot, autosave (quest-complete + quit + every 10 turns), and minimal
runtime-togglable settings (color/glyph mode).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
