/**
 * The set of plugins available to every viewer on the page.
 *
 * Registration is deliberately one-way. There is no `unregisterPlugin` and no
 * `clearPlugins`: plugins are registered once at startup, by the host or by
 * `window.MangoViewerPlugins`, and the registry is process-global rather than
 * scoped to a viewer instance. Registering the same id twice replaces the
 * earlier entry, which is the only removal this needs.
 *
 * Both removal functions did exist and neither was ever called. They are gone
 * on purpose — the missing `unregister` beside a published `register` is a
 * decision, not an omission. Adding one back means answering what it should do
 * to viewers already mounted with that plugin, which nothing currently needs.
 */
import type { ViewerPlugin } from '../core/types/plugin';
export declare const pluginsStore: {
    subscribe: (this: void, run: import("svelte/store").Subscriber<ViewerPlugin[]>, invalidate?: () => void) => import("svelte/store").Unsubscriber;
};
export declare const registerPlugin: (plugin: ViewerPlugin) => void;