ink-cartridge API docs

FrameworkCore ink-cartridge framework — screen, keyboard Keyboard EngineFramework-agnostic keyboard event engine i18n@cartridge-engine/i18n — LanguageProvider, useI18n Theme@cartridge-engine/theme — ThemeProvider, useTheme Event@cartridge-engine/event — EventBus, EventProvider 📘 Hand-written GuidesHow to use each API