adds a source uid to most damage & mobstate events (#11559)

Co-authored-by: Flipp Syder <76629141+vulppine@users.noreply.github.com>

Content.Server/Damage/Systems/DamageUserOnTriggerSystem.cs

@@ -35,7 +35,7 @@ public sealed class DamageUserOnTriggerSystem : EntitySystem
         var ev = new BeforeDamageUserOnTriggerEvent(damage, target);
         RaiseLocalEvent(source, ev);
 
-        return _damageableSystem.TryChangeDamage(target, ev.Damage, component.IgnoreResistances) is not null;
+        return _damageableSystem.TryChangeDamage(target, ev.Damage, component.IgnoreResistances, origin: source) is not null;
     }
 }