/**
 * Sanitizes a "directory path" value (relative path).
 * - normalizes to NFD
 * - strips diacritics
 * - keeps only [a-zA-Z0-9._-] in segments
 * - prevents empty segments, ".", "..", and leading dots
 * - joins segments with forward slashes
 */
export declare function sanitizePathDir(input: string): string;
/**
 * Sanitize an Admin (Media Library) folder name.
 * Rules:
 * - NFD normalize
 * - remove diacritics
 * - allow only: a-zA-Z0-9, space, underscore, hyphen
 * - collapse multiple spaces
 * - trim
 */
export declare function sanitizeAdminFolderName(input: string): string;
/**
 * Sanitize an Admin (Media Library) folder path like "a/b/c".
 */
export declare function sanitizeAdminFolderPath(input: string): string;
export declare function normalizeRelativeSlashPath(v: unknown): string;
export declare function safeResolveUnderRoot(root: string, rel: string): string | null;
/**
 * Best-effort cleanup of empty directories under `root`.
 * Attempts to remove parents of `absFilePath` until it reaches `root` or finds a non-empty dir.
 */
export declare function cleanupEmptyDirs(absFilePath: string, root: string): Promise<void>;