Add Price Volume Trend (PVT) Indicator and Tests

- Implemented the PvtIndicator class for calculating Price Volume Trend in Quantower.
- Created unit tests for the Pvt class to validate calculations and state management.
- Added validation tests to ensure consistency with OoplesFinance's implementation.
- Developed a comprehensive documentation (Pvt.md) explaining the PVT concept, calculations, and usage.
- Included methods for batch calculations and streaming updates for PVT.

lib/volume/pvt/Pvt.Quantower.cs

@@ -0,0 +1,50 @@
+using System.Drawing;
+using System.Runtime.CompilerServices;
+using TradingPlatform.BusinessLayer;
+
+namespace QuanTAlib;
+
+[SkipLocalsInit]
+public sealed class PvtIndicator : Indicator, IWatchlistIndicator
+{
+    [InputParameter("Show cold values", sortIndex: 21)]
+    public bool ShowColdValues { get; set; } = true;
+
+    private Pvt _pvt = null!;
+    private readonly LineSeries _series;
+
+#pragma warning disable S2325 // Instance property required by Quantower indicator interface
+    public int MinHistoryDepths => 2;
+#pragma warning restore S2325
+    int IWatchlistIndicator.MinHistoryDepths => 2;
+
+    public override string ShortName => "PVT";
+    public override string SourceCodeLink => "https://github.com/mihakralj/QuanTAlib/blob/main/lib/volume/pvt/Pvt.Quantower.cs";
+
+    public PvtIndicator()
+    {
+        OnBackGround = true;
+        SeparateWindow = true;
+        Name = "PVT - Price Volume Trend";
+        Description = "Price Volume Trend tracks cumulative buying/selling pressure weighted by relative price changes";
+
+        _series = new LineSeries(name: "PVT", color: Color.DarkGreen, width: 2, style: LineStyle.Solid);
+        AddLineSeries(_series);
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    protected override void OnInit()
+    {
+        _pvt = new Pvt();
+        base.OnInit();
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    protected override void OnUpdate(UpdateArgs args)
+    {
+        TBar bar = this.GetInputBar(args);
+        TValue result = _pvt.Update(bar, args.IsNewBar());
+
+        _series.SetValue(result.Value, _pvt.IsHot, ShowColdValues);
+    }
+}