Refactor event handling and improve argument validation across indicators

- Updated event handler signatures to use TValueEventArgs for consistency in Mama, Mgdi, Pwma, Rma, Sma, Ssf, Super, T3, Tema, Trima, Usf, Vidya, Wma, and Atr classes.
- Enhanced argument validation by specifying parameter names in exceptions for clarity.
- Adjusted tests to align with new event handler signatures.
- Improved code readability and maintainability by using structured records and lambda expressions.

lib/statistics/linreg/LinReg.cs

@@ -36,9 +36,11 @@ public sealed class LinReg : AbstractBase
     private readonly double _sum_x;
     private readonly double _denominator;
 
+    [StructLayout(LayoutKind.Auto)]
     private record struct State(double SumY, double SumXY, double SumY2, double LastVal, double LastValidValue);
     private State _state;
     private State _p_state;
+    private readonly TValuePublishedHandler _handler;
 
     private int _tickCount;
     private const int ResyncInterval = 1000;
@@ -81,6 +83,7 @@ public sealed class LinReg : AbstractBase
         _buffer = new RingBuffer(period);
         Name = $"LinReg({period})";
         WarmupPeriod = period;
+        _handler = Handle;
 
         // Precalculate constants
         // sum_x = 0 + 1 + ... + (n-1) = n(n-1)/2
@@ -95,9 +98,12 @@ public sealed class LinReg : AbstractBase
 
     public LinReg(ITValuePublisher source, int period, int offset = 0) : this(period, offset)
     {
-        source.Pub += (item) => Update(item);
+        source.Pub += _handler;
     }
 
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private void Handle(object? sender, TValueEventArgs args) => Update(args.Value, args.IsNew);
+
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     private double GetValidValue(double input)
     {
@@ -250,7 +256,7 @@ public sealed class LinReg : AbstractBase
         }
 
         Last = new TValue(input.Time, result);
-        PubEvent(Last);
+        PubEvent(Last, isNew);
         return Last;
     }
 
@@ -329,7 +335,7 @@ public sealed class LinReg : AbstractBase
     public static void Calculate(ReadOnlySpan<double> source, Span<double> output, int period, int offset = 0, double initialLastValid = 0)
     {
         if (source.Length != output.Length)
-            throw new ArgumentException("Source and output must have the same length");
+            throw new ArgumentException("Source and output must have the same length", nameof(output));
         if (period <= 0)
             throw new ArgumentException("Period must be greater than 0", nameof(period));