Book covers now recover after a failed extraction. Missing or damaged cover files are rebuilt when the library scans the book.
Supported accents now display correctly when a title stores the letter and accent separately. Text width and wrapping use the same result.
Works with current companion apps. No new phone app is required. This firmware works on both X3 and X4.
Thanks to Roberto Salas for the cover diagnosis and accent contribution in #61 and #62.
Validation: host regression tests and X3/X4 builds passed. X4 USB tests verified cover recovery and exact framebuffer output. X3 hardware checks and camera checks remain incomplete.