Sky-high costs continue to drive talented chefs to Boston’s suburbs. Newtonites are among the beneficiaries, as Sycamore offers something they once had to venture into the city for. In this cozy Newton Centre bistro, chefs David Punch and Lydia Reichert and bar manager Scott Shoer offer serious cocktails, carefully crafted small plates, quality charcuterie, delicious vegetarian dishes and beautiful large-format meat and seafood platters. Bostonians lamenting this exodus can comfort themselves that at least it’s not in Belchertown.