Add pulse contract and isolation valves

src/ReactorMaintenance.Simulation/Difficulties/NormalBalancing.cs

@@ -6,6 +6,7 @@ public class NormalBalancing : Balancing
     public override int DefaultLevelHeight => 12;
     public override int MinimumLevelSize => 4;
     public override int ForecastHorizon => 6;
+    public override int StepsPerPulse => 3;
     public override float MinValue => 0;
     public override float MaxValue => 10;
     public override float FuelSafe => 1.5f;