remove private constructor, no longer needed bcs of "required"

csharp/Lib/Units/Composite/Ac3Bus.cs

@@ -1,11 +1,8 @@
 
 namespace InnovEnergy.Lib.Units.Composite;
 
-
-public sealed class Ac3Bus
+public class Ac3Bus
 {
-    private Ac3Bus() {}
-
     public required AcPhase   L1        { get; init; }
     public required AcPhase   L2        { get; init; }
     public required AcPhase   L3        { get; init; }

csharp/Lib/Units/Composite/AcPhase.cs

@@ -5,8 +5,6 @@ namespace InnovEnergy.Lib.Units.Composite;
 
 public sealed class AcPhase 
 {
-    private AcPhase(){}
-    
     public required Voltage Voltage { get; init; } 
     public required Current Current { get; init; } 
     public required AcPower Power   { get; init; } 

csharp/Lib/Units/Composite/AcPower.cs

@@ -98,13 +98,10 @@ public sealed class AcPower
 
     public static AcPower operator -(AcPower p)
     {
-        var activePower   = -p.Active;
-        var reactivePower = -p.Reactive;
-        
         return FromActiveReactive
         (
-            activePower,   
-            reactivePower  
+            -p.Active,   
+            -p.Reactive  
         );
     }