feat: Straight vertical line

Author: YCode

YCode.Designer.Demo/Demo/Playground/Playground.xaml

@@ -38,6 +38,7 @@
                              Mounting="OnMounting"
                              Mounted="OnMounted"
                              GridType="Dot"
+                             Orientation="Vertical"
                              ToolTemplate="{StaticResource ToolDataTemplate}"
                              ItemContainerStyle="{StaticResource FluxoNodeStyle}"
                              Source="{Binding Source}" />

YCode.Designer.Fluxo/Lines/Impl/FluxoStraightLine.cs

@@ -35,7 +35,20 @@ protected override void OnHorizontal()
 
     protected override void OnVertical()
     {
-        throw new NotImplementedException();
+        this.Parameter.Start = this.Parameter.Source.Top;
+
+        this.Parameter.End = this.Parameter.Target.Top;
+
+        if (this.Parameter.Source.Bottom.X < this.Parameter.Target.Top.X)
+        {
+            this.Parameter.Start = this.Parameter.Source.Bottom;
+        }
+        else if (this.Parameter.Target.Bottom.X < this.Parameter.Source.Top.X)
+        {
+            this.Parameter.End = this.Parameter.Target.Bottom;
+        }
+
+        this.Points.AddRanage([this.Parameter.Start, this.Parameter.End]);
     }
 
     protected override void OnCross()