SUNRISE, Fla. — Justin Brazeau is a big man. “They said there’s a chance,” Brazeau said of the medical staff. “It’s a huge, huge help from the mental side of an injury,” Brazeau said of team immersion. “What you’re noticing now,” said Bruins coach Jim Montgomery, “is something we think is part of him.” The 26-year-old earned his Bruins opportunity, …