It’s the encore of a lifetime. Jesse Findling, a 20-year-old Long Island man who captured the nation’s heart by defying a lifelong stutter to soar his way to the top 12 of “American Idol,” has enjoyed a life-changing hero’s welcome since returning home. “It wasn’t just about singing for me,” the Massapequa Park sensation told The Post minutes before belting out the National Anthem at the NHL Islanders’ season finale last week – his largest-ever live crowd. “Doing things like this, I feel like I