/**
 * Opens IndexedDB and runs onupgradeneeded to create stores and indexes.
 * Singleton per (name, version).
 * @module indexedDB/openDB
 */
import type { IndexedDBConfig } from "./types";
/**
 * Opens the database and creates/upgrades object stores and indexes from config.
 * Uses a singleton cache per (name, version); repeated calls with the same config reuse the same connection.
 */
export declare function openDB(config: IndexedDBConfig): Promise<IDBDatabase>;