The value of Zoom Video Communications Inc. surpassed Pinterest Inc.'s on Thursday as both companies made their stock-market debuts. The market cap of San Jose-based cloud-based video communications company Zoom ended its first day of trading on Nasdaq at nearly $16 billion. That handily topped the valuation of just under $13 billion given to San Francisco-based Pinterest at the end of its first trading day on the New York Stock Exchange. Both companies topped their IPO targets and their shares…