Don't increase broken bones stat when bones are already broken

[haveric]

Summary

Bugfixes "Don't increase broken bones stat when bones are already broken"

Purpose of change

Fixes #54069

Describe the solution

Check to see if the bone was broken before applying damage and only increase the stat on newly broken bones

Describe alternatives you've considered

None

Testing

Debug damaged myself a limb. Continually damaging the limb after being broken no longer increased the stat.
Debugged limb health back and damaged it again, stat still increases.

Additional context

[anothersimulacrum]

This looks like it will crash if a monster is damaged - as_character can only be used if the creature is a character, and monsters are not.

[haveric]

This looks like it will crash if a monster is damaged - as_character can only be used if the creature is a character, and monsters are not.

I didn't notice any issues when testing, but I added another avatar check for safety either way.