Add a new Complete the Sentence quiz type that renders a Spanish example
sentence from the card with the target word blanked out and asks the
student to pick the missing word from 4 choices (other cards' fronts
from the same week's pool).
Core logic lives in SharedModels/SentenceQuizEngine as pure functions
over VocabCard, covered by 18 Swift Testing tests. CourseQuizView calls
the engine, pre-filters the card pool to cards that can produce a
resolvable blank, and reuses the existing MC rendering via a new
correctAnswer(for:) helper.
VocabCard gains examplesBlanks (parallel array to examplesES) so content
can explicitly tag the blanked substring; DataLoader reads an optional
"blank" key on each example. Additive schema change, CloudKit-safe
default.
Also adds ContentCoverageTests that parse the repo's course_data.json
and assert every card has >=3 examples and yields a resolvable question.
These tests currently fail: 1,117 cards still need sentences. They are
the oracle for the gap-fill pass that follows.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
