feat(ui): add WorkConsole detail component

Standalone terminal-styled card with traffic-light title bar, roadblock
band, and three tabs (Output / Actions / Session). Renders fully via
design-time sample data; does not touch DetailsIslandView.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/ClaudeDo.Ui/Views/Islands/Detail/WorkConsole.axaml.cs

@@ -0,0 +1,8 @@
+using Avalonia.Controls;
+
+namespace ClaudeDo.Ui.Views.Islands.Detail;
+
+public partial class WorkConsole : UserControl
+{
+    public WorkConsole() => InitializeComponent();
+}