/**
 * Returns the URL of the FeatureServer endpoint for a given item URL.
 *
 * - If the input URL is empty or falsy, returns an empty string.
 * - If the URL already ends with '/FeatureServer', returns it as is.
 * - If the URL ends with a trailing slash, removes it.
 * - If the URL ends with a layer or table index (e.g., '/0'), removes the index.
 *
 * @param itemUrl - The URL of the item to process.
 * @returns The normalized FeatureServer URL.
 */
export declare const getFeatureServerRootURL: (itemUrl: string, amdinEndPoint?: boolean) => string;