/**
 * Detect a long blocking sleep in a bash command and return an advisory notice,
 * or `undefined` if the command does not contain a qualifying sleep. The notice
 * is appended to the bash result output; it never blocks execution.
 *
 * `timeoutSec` is the effective (already-clamped) execution timeout the command
 * will run under, when known. The bash tool kills the command at this timeout
 * whether the sleep fits inside it or not. Passing it lets the notice report
 * the bounded effective silent wait the operator will actually observe, instead
 * of the requested duration (which may be much longer and is never reached).
 * When `timeoutSec` is `undefined` (no timeout known at the construction
 * boundary), the notice reports only the requested duration and stays useful.
 */
export declare function longSleepAdvisory(command: string, timeoutSec?: number): string | undefined;