PROVIDENCE, R.I. — Handmade paper flags, grouped by color, fluttered around the railing at the Waterplace Park stage, suggesting Tibetan prayer flags had formed a rainbow that was flattened by the intense heat of the melting pot.Speaking silently for peace, the flags played a role in celebrating the United Nations International Day of Peace, which was Friday, extended to a month of activities, including a performance of Marc Levitt's "Triple Decker" on Sunday."Triple [...]