Add eventing support to WMA indicator and implement unit tests for various indicators

- Enhanced WMA indicator with event-driven capabilities using ITValuePublisher interface.
- Created a new TODO file listing various indicators and their corresponding libraries.
- Added unit tests for DEMA, HMA, TEMA, and WMA indicators to ensure proper functionality.
- Implemented tests for handling new bars, ticks, and historical data updates across indicators.
- Verified that indicators correctly compute values and handle different source types.

lib/averages/dema/Dema.Coverage.Tests.cs

@@ -0,0 +1,87 @@
+using System;
+using Xunit;
+
+namespace QuanTAlib.Tests;
+
+public class DemaCoverageTests
+{
+    [Fact]
+    public void Dema_CompensationLogic_IsTriggered()
+    {
+        // Compensation happens when E <= 1e-10
+        // E starts at 1.0 and decays by (1-alpha) each step.
+        // We need enough steps to reach 1e-10.
+        // If period=10, alpha ~ 0.18, decay ~ 0.81
+        // 0.81^n <= 1e-10 => n * log(0.81) <= -10
+        // n * -0.09 <= -10 => n >= 111
+        
+        int count = 200;
+        int period = 10;
+        var dema = new Dema(period);
+        
+        for (int i = 0; i < count; i++)
+        {
+            dema.Update(new TValue(DateTime.UtcNow, 100.0));
+        }
+        
+        // Just ensuring no exception and value is correct
+        Assert.Equal(100.0, dema.Last.Value, 1e-9);
+    }
+
+    [Fact]
+    public void Dema_IsHot_Logic()
+    {
+        // IsHot happens when E <= 0.05
+        // 0.81^n <= 0.05 => n >= 14
+        
+        int period = 10;
+        var dema = new Dema(period);
+        
+        Assert.False(dema.IsHot);
+        
+        for (int i = 0; i < 50; i++)
+        {
+            dema.Update(new TValue(DateTime.UtcNow, 100.0));
+            if (i > 30) // Should be hot by now
+            {
+                Assert.True(dema.IsHot);
+            }
+        }
+    }
+
+    [Fact]
+    public void Dema_StaticCalculate_Alpha_Coverage()
+    {
+        double[] source = new double[100];
+        double[] output = new double[100];
+        for(int i=0; i<100; i++) source[i] = 100.0;
+        
+        // Use alpha overload
+        Dema.Calculate(source.AsSpan(), output.AsSpan(), 0.1);
+        
+        Assert.Equal(100.0, output[^1], 1e-9);
+    }
+
+    [Fact]
+    public void Dema_Reset_ClearsState()
+    {
+        var dema = new Dema(10);
+        dema.Update(new TValue(DateTime.UtcNow, 100.0));
+        Assert.NotEqual(0, dema.Last.Value);
+        
+        dema.Reset();
+        
+        Assert.Equal(0, dema.Last.Value);
+        Assert.False(dema.IsHot);
+    }
+    
+    [Fact]
+    public void Dema_Constructor_Alpha_Validation()
+    {
+        Assert.Throws<ArgumentException>(() => new Dema(0.0));
+        Assert.Throws<ArgumentException>(() => new Dema(1.1));
+        
+        var dema = new Dema(0.5);
+        Assert.NotNull(dema);
+    }
+}