2025-07-15: Fighter states

Worked on the fighter state machine. For now we’ll have three states:

• Idle
• Move to location
• Attack

Each state is a superset of the other. To simplify the logic, I’ve let the fighters move in a 6DOF Descent-like style. This skips having to put in attack runs. The fighters can just stop dead at their targets and shoot at them if no one else is around. Fighters will have an attack band within which they shoot. If they’re too close, we can just make them reverse.