A whale-watching trip off Cape Cod turned into the kind of encounter most people only dream about, as a cluster of whales surfaced and fed so close to the boat that passengers could barely contain their awe. The viral clip offers a glimpse of just how breathtaking a day on the water can be when nature decides to put on a show. What happened? Near Provincetown, Massachusetts, a whale-watching excursion became the setting for a widely shared TikTo…