The ocrs crate's default alphabet has an E where its recognition model was
trained with € (ocrs-models DEFAULT_ALPHABET), so a scanned "€250" was
recognised as "E250". pdfcraft-ocr now gives ocrs the alphabet the model was
trained with.
the_alphabet_is_the_trained_one checks the alphabet without the models;
recognize_text_reads_the_euro_sign reads a scan end to end when they are
installed.
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>