/**
 * Selective Unicode ligature decomposition for epub-to-markdown conversion.
 *
 * Decomposes only the Latin typographic ligatures (U+FB00–FB06) that are
 * commonly embedded in epub/PDF content:
 *
 *   U+FB00 ff → ff
 *   U+FB01 fi → fi
 *   U+FB02 fl → fl
 *   U+FB03 ffi → ffi
 *   U+FB04 ffl → ffl
 *   U+FB05 ſt → st  (long-s t)
 *   U+FB06 st → st
 *
 * Unlike blanket NFKC normalization, this approach does NOT alter:
 *   - CJK fullwidth punctuation (，：？！（） etc.)
 *   - Circled/enclosed characters (① ② ③ etc.)
 *   - Superscript/subscript digits (² ³ etc.)
 *   - Other compatibility mappings
 *
 * This runs AFTER the HTML-to-Markdown conversion step so that structural
 * Markdown syntax (headings, links, images) is already in place and only
 * the text content is affected.
 *
 * No external dependencies — pure string replacement.
 */
/**
 * Decompose Latin typographic ligatures to their ASCII equivalents.
 *
 * @param text - Markdown text that may contain ligature codepoints
 * @returns Text with ligatures replaced by their component letters
 */
export declare function normalizeUnicode(text: string): string;