import { BaseStorageAdapter } from './StorageAdapter.cjs';
export declare class IndexedDBAdapter extends BaseStorageAdapter {
    private dbName;
    private storeName;
    private db;
    constructor(dbName?: string, storeName?: string);
    /**
     * Probe IndexedDB availability by attempting to open a test database.
     * This catches private mode and other restrictions that block IndexedDB.
     */
    static probe(): Promise<{
        available: boolean;
        error?: Error;
    }>;
    private openDB;
    private getStore;
    get(key: string): Promise<string | null>;
    set(key: string, value: string): Promise<void>;
    delete(key: string): Promise<void>;
    keys(): Promise<Array<string>>;
    clear(): Promise<void>;
}