The fighter is a strike craft: a small, fast craft with built-in guns. A Shipyard builds it from composite, a thruster and steel plate, as an item that goes into the station's hold rather than as a ship.
A ship fitted with a hangar launches fighters in a fight, each loaded with rounds from that ship's hold. Each flies from its carrier on its own. A fighter's guns aim only at other strike craft. When the fight ends, it lands on its carrier and returns to the hold as an item, and the carrier repairs any damage from its own hold.