/** References in the retained toolbox are internal Wiki media, displayed as derivatives. */
export function referencePreview(source:string){
 const path=new URL(source,'http://wiki.internal').pathname;
 if(!/^\/api\/media\/[0-9a-f-]{36}$/.test(path))throw Error('Invalid reference media');
 return '/api/preview?'+new URLSearchParams({source:path,width:'960'});
}