/**
 * dsh-widgets — the preference WRITE path.
 *
 * Every write is one transaction with two sinks:
 *   1. localStorage, the fast per-origin cache, written immediately; and
 *   2. the host file (`/api/widgets-state`), written through a 400 ms debounce
 *      and flushed with `sendBeacon` when the page is being torn down.
 *
 * The localStorage mirror lives in this module (rather than in
 * `runtime/prefs.ts`) because it shares the SAME timestamp as the host write:
 * whichever sink is newer decides the winner at boot, so the two writes cannot be
 * separated without splitting that decision.
 */
import { type Prefs } from './prefs';
/** Same-origin host route holding the authoritative state file. */
export declare const STORE_API = "/api/widgets-state";
export declare function putState(s: Prefs, at: number): Promise<void>;
export declare function saveState(s: Prefs): void;
/**
 * Flush any state that has not yet reached the host store when the page is
 * being torn down (window/tab close, navigation, desktop-app quit). The
 * 400 ms debounce means the last edit before a quick close is usually still
 * pending here; a normal fetch would be cancelled with the page, but
 * `sendBeacon` is delivered by the browser even as the page is destroyed —
 * which is what keeps the write inside desktop shells that spawn a fresh
 * random loopback origin on every launch (their localStorage is a new realm
 * each boot, so the host file is the only channel that survives).
 */
export declare function flushPendingState(): void;