feat: add transition based number displayer.

src/Ursa.Themes.Semi/Controls/NumberDisplayer.axaml

@@ -0,0 +1,15 @@
+<ResourceDictionary
+    xmlns="https://github.com/avaloniaui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:converters="clr-namespace:Ursa.Converters;assembly=Ursa"
+    xmlns:u="https://irihi.tech/ursa">
+    <!--  Add Resources Here  -->
+    <ControlTheme x:Key="{x:Type u:NumberDisplayerBase}" TargetType="u:NumberDisplayerBase">
+        <Setter Property="Duration" Value="0:0:0.2" />
+        <Setter Property="Template">
+            <ControlTemplate TargetType="u:NumberDisplayerBase">
+                <TextBlock Text="{TemplateBinding InternalText, Mode=OneWay}" />
+            </ControlTemplate>
+        </Setter>
+    </ControlTheme>
+</ResourceDictionary>