Brandon Bussi understands the situation. The Bruins’ internal competition doesn’t just extend to the depths of the forward core. With Linus Ullmark and Jeremy Swayman’s positions on the NHL depth chart rather solidified, the 25-year-old Bussi enters training camp as one of four goaltenders – himself, Kyle Keyser, Michael DiPietro and Shane Starrett – looking to leave a strong impression in Boston before likely plying their trades in the minors.