/**
 * `withDeadline` — race a promise against a timer, returning a
 * `{ timedOut }` envelope (#86).
 *
 * Promoted from homes-mcp's `src/tools/deadline.ts` (#54/#56). The MCP
 * SDK gives each tool call a finite request deadline (60s default); a
 * fetch with no shorter effective deadline can wedge the connection
 * into a `-32001 Request timed out`. Wrapping the inner work in a
 * deadline comfortably below the MCP timeout turns "hang until the
 * client kills the connection" into "return partial results with
 * per-row markers".
 *
 * Pure: no I/O, no logging. The timer is always cleared (and unref'd)
 * so a fast inner promise never keeps the process alive for the full
 * deadline, and inner rejections propagate rather than being folded
 * into a timeout.
 */
/** Discriminated outcome of a deadline race. */
export type DeadlineOutcome<T> = {
    timedOut: false;
    value: T;
} | {
    timedOut: true;
};
/**
 * Race `inner` against a `ms` timer.
 *
 *   * Inner resolves first → `{ timedOut: false, value }`.
 *   * Timer fires first     → `{ timedOut: true }` (the inner promise is
 *                             left to settle in the background; its
 *                             eventual result/rejection is ignored).
 *   * Inner rejects first   → the rejection propagates (NOT folded into
 *                             a timeout) so per-row try/catch still sees
 *                             the real error.
 *
 * The timer is cleared as soon as either side wins, and `unref`'d so it
 * can't hold the event loop open on its own.
 *
 * @param inner  The promise to race.
 * @param ms     Deadline in milliseconds.
 */
export declare function withDeadline<T>(inner: Promise<T>, ms: number): Promise<DeadlineOutcome<T>>;