```ts
export function chunk<T>(items: readonly T[], size: number): T[][] {
  if (!Number.isInteger(size) || size <= 0) {
    throw new Error('Size must be a positive integer');
  }

  return items.length === 0 ? [] : 
    Array.from({ length: Math.ceil(items.length / size) }, (_, i) => 
      items.slice(i * size, (i + 1) * size)
    );
}
```