ac84b22977
Opening a book chapter froze the app in an infinite render loop. Root
cause: the books screens used the eager `NavigationLink { destination }`
form inside `List`/`LazyVStack`. That form keeps the destination view
structurally parented to the source row, so `BookReaderView`'s ScrollView
got trapped inside a `List` row — a row sizes to intrinsic height, a
ScrollView has none, so the two never converge and re-measure forever.
Switch the whole books navigation chain to value-based navigation:
- practiceHomeView, BookLibraryView, BookChapterListView use
NavigationLink(value:).
- PracticeView's NavigationStack declares the BooksRoute, Book, and
BookChapter destinations once, at the stack root (mixing eager and
value-based pushes in one path caused pushed screens to pop back).
- BookReaderView is built from just a BookChapter; it resolves its Book
by slug via @Query.
Also:
- BookChapter gains a stored paragraphCount so the chapter list no longer
decodes the full paragraph JSON on every render (bookDataVersion -> 6
to re-seed).
- BookSpeechController builds its AVSpeechSynthesizer lazily.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>