/** Single-line browse rows — matches `--bp-size-090` (36px) in taxonomy-menu-item styles. */
export declare const ESTIMATED_BROWSE_ROW_HEIGHT = 36;
/**
 * Two-line search/ancestor rows — display name + breadcrumb line.
 * ~20px body-default-bold + ~16px xsmall breadcrumb + 2 × 4px vertical padding ≈ 44px.
 */
export declare const ESTIMATED_SEARCH_ROW_HEIGHT = 44;
/**
 * How many off-screen rows the virtualizer renders above and below the
 * viewport. Higher values reduce the chance of fast scroll outrunning
 * the renderer at the cost of slightly more DOM work; rows are memoized,
 * so the trade-off favors a generous cushion.
 */
export declare const OVERSCAN_COUNT = 20;
/** Skeleton rows shown during initial load. Sized to fill the stable 21rem popover area. */
export declare const SKELETON_ROW_COUNT = 9;
/** Height (px) of each skeleton row Ghost placeholder. */
export declare const SKELETON_ROW_HEIGHT = 16;
/** Number of ghost rows shown at the bottom of the list while a "load more" page is in flight. */
export declare const LOAD_MORE_GHOST_ROW_COUNT = 3;
/** Height (px) of each ghost row shown during "load more". */
export declare const LOAD_MORE_GHOST_ROW_HEIGHT = 16;
/** Total height (px) of the inline "load more" ghost block: padding(12×2) + 3×16 + 2×gap(20) = 112. */
export declare const LOAD_MORE_GHOST_BLOCK_HEIGHT = 112;
/** Distance (px) from the bottom of the list at which the next page is pre-fetched. */
export declare const LOAD_MORE_ROOT_MARGIN_PX = 200;
/** Minimum time the load-more loading slot stays visible before yielding to the inline error row. */
export declare const LOAD_MORE_ERROR_MIN_VISIBLE_MS = 400;
/** Separator string rendered between breadcrumb segments. */
export declare const BREADCRUMB_SEPARATOR = " / ";
/** Maximum number of lines the breadcrumb trail may occupy before collapsing to `first / icon / last`. */
export declare const BREADCRUMB_MAX_LINES = 2;
/**
 * Sub-pixel tolerance for breadcrumb overflow detection.
 * Browsers can report ~1px diffs even when content visually fits.
 */
export declare const BREADCRUMB_OVERFLOW_THRESHOLD_PX = 2;
/** Unicode ellipsis character used when trimming overflowed breadcrumb segments. */
export declare const BREADCRUMB_ELLIPSIS_CHAR = "\u2026";
/** Default page size for taxonomy node fetch requests. */
export declare const DEFAULT_PAGE_LIMIT = 100;
/** Stale-after threshold for cached levels; older entries are evicted on read. */
export declare const CACHE_TTL_MS: number;
/** Cache key used for the root level (parentId === null). */
export declare const ROOT_CACHE_KEY = "__root__";
/** Sentinel `Crumb.id` for the synthetic root entry; mapped back to `null` parentId by the shell. */
export declare const BREADCRUMB_ROOT_ID = "__breadcrumb_root__";
/** Debounce time for search input changes. */
export declare const SEARCH_DEBOUNCE_MS = 500;