feat: initialize breadcrumb.

src/Ursa/Controls/Breadcrumb/BreadcrumbItem.cs

@@ -0,0 +1,41 @@
+using System.Windows.Input;
+using Avalonia;
+using Avalonia.Controls;
+
+namespace Ursa.Controls;
+
+public class BreadcrumbItem: ContentControl
+{
+    public static readonly StyledProperty<object?> SeparatorProperty =
+        AvaloniaProperty.Register<BreadcrumbItem, object?>(
+            nameof(Separator), "/");
+
+    public object? Separator
+    {
+        get => GetValue(SeparatorProperty);
+        set => SetValue(SeparatorProperty, value);
+    }
+
+    public static readonly StyledProperty<object?> IconProperty = AvaloniaProperty.Register<BreadcrumbItem, object?>(
+        nameof(Icon));
+
+    public object? Icon
+    {
+        get => GetValue(IconProperty);
+        set => SetValue(IconProperty, value);
+    }
+
+    public static readonly StyledProperty<ICommand?> CommandProperty = AvaloniaProperty.Register<BreadcrumbItem, ICommand?>(
+        nameof(Command));
+
+    public ICommand? Command
+    {
+        get => GetValue(CommandProperty);
+        set => SetValue(CommandProperty, value);
+    }
+
+    static BreadcrumbItem()
+    {
+        
+    }
+}