Add calculation overrides

[BarmonHammer]

Currently there is no way to set:

• damage already dealt
• current mag size
• over shield health

We should have a function that sets these values globally so all stat_calcs get affected with one call.

This may require CalculationInput to be revamped.

[oh-yes-0-fps]

I believe reload override can do the current mag size technically. Damage already dealt I would be interested to know the main use case. Overshield is something to look into but it should probably be packaged with a "statuseffect "system that brings you very close to an ecs...