Function useVirtualRows

useVirtualRows(options: UseVirtualRowsOptions): UseVirtualRowsResult
Fixed-height row windowing.
Parameters
- options: UseVirtualRowsOptions
  Row count, row height and overscan.
Returns UseVirtualRowsResult
The visible window plus the handlers that maintain it.
Remarks
Fixed heights are a deliberate constraint: they make the visible range O(1) to compute and remove the measure-then-reflow pass that variable heights force. Scroll position is tracked in a ref and only promoted to state when the computed window actually changes, so scrolling within a single row re-renders nothing.
Example
```
const { window, totalHeight, onScroll, setViewportHeight } = useVirtualRows({
  rowCount: rows.length,
  rowHeight: 36,
});

<div onScroll={onScroll} style={{ overflow: 'auto' }}>
  <div style={{ height: totalHeight }}>
    {rows.slice(window.startIndex, window.endIndex).map(renderRow)}
  </div>
</div>
```
- Defined in core/useVirtualRows.ts:66