/**
 * @file
 *
 * Converts an error into a human-readable string with its full stack trace,
 * recursive `cause` chain, and the aggregated errors of an `AggregateError`.
 *
 * Used Node-side by the framework global-setup/teardown to log non-fatal
 * cleanup errors. It is a hand-kept copy of `obsidian-dev-utils`' `errorToString`
 * (`src/error.ts`) — see the sync rule L17 — so the two stay behaviorally
 * identical without the harness taking a dependency on the utility library.
 */
/**
 * Converts an error to a string representation, including nested causes and the
 * aggregated errors of an `AggregateError`, with each nested error rendered as
 * `    at` separator lines so it blends into the surrounding stack.
 *
 * @param error - The error to convert to a string.
 * @returns The string representation of the error.
 */
export declare function errorToString(error: unknown): string;