Generate one-paragraph Spanish stories on-device using Foundation Models,
matched to user's level and enabled tenses. Every word is tappable —
pre-annotated words show instantly, others get a quick on-device AI
lookup with caching. English translation hidden by default behind a
toggle. Comprehension quiz with 3 multiple-choice questions. Stories
saved to cloud container for sync and persistence across resets.
Closes#9
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>