/**
 * Returns the locale to use based on what has been released. Matches on the
 * language part of the locale (before the "-") so that regional variants like
 * "en-ca" or "es-us" resolve correctly:
 *
 * - "en-ca" → "en-ca"  (language "en" is released; full locale preserved)
 * - "es-us" → "es-us"  (language "es" is released; full locale preserved)
 * - "fr"    → "en"     (language "fr" not released; falls back to "en")
 *
 * Note: expects a normalized locale (lower-case, hyphens not underscores).
 */
export declare function getReleasedLocale(locale: string): string;