refactor: optimize event args handling for performance improvements

lib/statistics/linreg/LinReg.Validation.Tests.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Linq;
 using System.Runtime.CompilerServices;
 using Xunit;

lib/statistics/linreg/LinReg.cs

@@ -102,7 +102,7 @@ public sealed class LinReg : AbstractBase
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    private void Handle(object? sender, TValueEventArgs args) => Update(args.Value, args.IsNew);
+    private void Handle(object? sender, in TValueEventArgs args) => Update(args.Value, args.IsNew);
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     private double GetValidValue(double input)

lib/statistics/median/Median.cs

@@ -82,7 +82,7 @@ public sealed class Median : AbstractBase
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    private void Handle(object? sender, TValueEventArgs args) => Update(args.Value, args.IsNew);
+    private void Handle(object? sender, in TValueEventArgs args) => Update(args.Value, args.IsNew);
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     public override TValue Update(TValue input, bool isNew = true)

lib/statistics/stddev/StdDev.Validation.Tests.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Linq;
 using Xunit;
 using QuanTAlib;

lib/statistics/variance/Variance.Validation.Tests.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Linq;
 using Xunit;
 using QuanTAlib;