import type { AppRequestHeaders } from "./types.js";
/** Sync locale/timezone into module state for HTTP clients (via `getAppRequestHeaders`). */
export declare function syncAppRequestHeaders(headers: Partial<AppRequestHeaders>): void;
/** Read current app preference headers — wire to API client `setAppHeaderProvider`. */
export declare function getAppRequestHeaders(): AppRequestHeaders;
/** Reset to defaults — for tests only. */
export declare function resetAppRequestHeaders(): void;