Like his masterly art, my friend István was charming, brilliant, mischievous, unique — and now, alas, he’s gone and zoomed away — In the 1990s, when magazines still consisted only of their paper editions, because the internet hadn’t yet changed everything (or practically anything), I took over the weekly New York. I orchestrated its reinvention from guggle to zatch, as Thurber would put it, including a new front section called Gotham, which…