WARWICK — Jeff Lavalley, operations manager at a pet food distribution company, came to Tuesday’s summit on hiring ex-convicts with a persuasive argument. That argument sat beside him.Dwayne Gibson served 13 years in federal prison for drugs. Almost five years ago, he turned up at Lavalley’s Cumberland business, Pet Food Experts, unable to make a cardboard box, Lavalley said — and he once drove a piece of loading equipment into a wall.But Gibson [...]