Fire damage system fixes (#37241)

Fire fixes

Content.Shared/Atmos/GetFireProtectionEvent.cs

@@ -29,5 +29,6 @@ public sealed class GetFireProtectionEvent : EntityEventArgs, IInventoryRelayEve
     public void Reduce(float by)
     {
         Multiplier -= by;
+        Multiplier = MathF.Max(Multiplier, 0f);
     }
 }

Content.Shared/Clothing/EntitySystems/FireProtectionSystem.cs

@@ -25,7 +25,7 @@ public sealed class FireProtectionSystem : EntitySystem
 
     private void OnArmorExamine(Entity<FireProtectionComponent> ent, ref ArmorExamineEvent args)
     {
-        var value = MathF.Round((1f - ent.Comp.Reduction) * 100, 1);
+        var value = MathF.Round(ent.Comp.Reduction * 100, 1);
 
         if (value == 0)
             return;