Safer NPC Ranged Weapon Use

[ShnitzelX2]

Summary

Bugfixes "safer NPC ranged weapon use"

Purpose of change

In my experience, NPC allies using guns are more dangerous than the monsters they fight. They tend to shoot the player and each other on accident, even with the "allies in line of fire" rule on.

I figured a good place to start was wont_hit_friend(), which makes three checks to see if an ally won't get hit by a shot:

1. weapon confidence < 1. This was described by a comment as badly extracting dispersion from ranged confidence.
2. range to target == 1. This is a faulty assumption, since bullets keep traveling after missing their target, and shots at range 1 are by no means guaranteed hits.
3. angle difference between ally and target is > 30 degrees (60 degrees for ally distance 2, 90 degrees for ally distance 1). 30 degrees is the maximum final dispersion, so we can do better.

There's additional problems: trajectories are inherently less accurate than dispersion angles at close range, and until #71605 is merged, trajectories won't line up with dispersion angles anyways.

Describe the solution

Corresponding to the list above:

1. removed completely (if there's a case where this matters and should still be in this function, let me know)
2. range == 1 is only assumed for throwing and NOT for guns, since throwing at range 1 is safe
3. angle differences use maximum weapon dispersion instead, removes close range check in favor of checking intended trajectory for allies

Describe alternatives you've considered

Testing

• passed all tests locally
• spawned three NPC allies with guns and tested various monster spawns with different engagement rules
• made sure turning "allies in line of fire" off still works
• made sure allies still could use melee, guns with bayonets

Additional context

This makes allies with guns fire more conservatively. As intended, you may have to turn the "allies in line of fire" rule off if you're getting mauled in melee by something and you want your ally to shoot an adjacent monster.