export declare function getActiveTimezone(): string;
/**
 * Format a Date as YYYY-MM-DD in the active (or supplied) timezone.
 * Uses `en-CA` locale because it formats as YYYY-MM-DD natively.
 */
export declare function localDateFor(date: Date, timezone?: string): string;
/** Today's YYYY-MM-DD in the active (or supplied) timezone. */
export declare function localDate(timezone?: string): string;
/**
 * Convert a YYYY-MM-DD date string into the UTC ISO timestamp for noon-local
 * time on that date in the active (or supplied) timezone.
 *
 * Replaces the legacy `${date}T12:00:00.000Z` shortcut, which was UTC noon
 * (= early morning for any user east of UTC, or evening for any user west).
 */
export declare function dateToNoonTimestamp(date: string | undefined, timezone?: string): string | undefined;