/**
 * Offline, deterministic placeholder image source.
 *
 * Replaces picsum.photos (unreachable in restricted / offline networks) with a
 * same-origin SVG generated by `/api/placeholder/[w]/[h]?seed=…`. Each seed yields
 * a stable, distinct gradient, so demo/fallback art still looks varied — and it
 * works with `next/image` with no external requests.
 */
export function placeholderSrc(
  seed: string | number,
  width: number,
  height: number
): string {
  return `/api/placeholder/${width}/${height}?seed=${encodeURIComponent(String(seed))}`;
}
