feat(ui): details island with agent strip, terminal, subtasks, notes

Adds AgentStripView (status/model/turns/tokens row, worktree path,
branch line, action buttons), SessionTerminalView (scrollable log with
auto-scroll on CollectionChanged, prompt TextBox with Enter binding),
and replaces DetailsIslandView placeholder with full ScrollViewer layout
containing editable title, agent strip, terminal, subtasks, notes.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/ClaudeDo.Ui/Views/Islands/AgentStripView.axaml

@@ -0,0 +1,39 @@
+<UserControl xmlns="https://github.com/avaloniaui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             xmlns:vm="using:ClaudeDo.Ui.ViewModels.Islands"
+             x:Class="ClaudeDo.Ui.Views.Islands.AgentStripView"
+             x:DataType="vm:DetailsIslandViewModel">
+  <Border Classes="agent-strip">
+    <StackPanel Margin="14,12" Spacing="6">
+      <!-- Row 1: status dot · status label · model · turns · tokens -->
+      <StackPanel Orientation="Horizontal" Spacing="10">
+        <Ellipse Width="8" Height="8" Fill="{DynamicResource MossBrush}" VerticalAlignment="Center"/>
+        <TextBlock Text="{Binding AgentStatusLabel}" FontSize="12"
+                   Foreground="{DynamicResource TextBrush}" VerticalAlignment="Center"/>
+        <TextBlock Text="{Binding Model}" FontFamily="{DynamicResource MonoFamily}"
+                   FontSize="11" Foreground="{DynamicResource TextDimBrush}" VerticalAlignment="Center"
+                   IsVisible="{Binding Model, Converter={x:Static ObjectConverters.IsNotNull}}"/>
+        <TextBlock Text="{Binding Turns, StringFormat='turns: {0}'}" FontSize="11"
+                   Foreground="{DynamicResource TextMuteBrush}" VerticalAlignment="Center"/>
+        <TextBlock Text="{Binding Tokens, StringFormat='tok: {0}'}" FontSize="11"
+                   Foreground="{DynamicResource TextMuteBrush}" VerticalAlignment="Center"/>
+      </StackPanel>
+      <!-- Row 2: worktree path -->
+      <TextBlock Text="{Binding WorktreePath}" FontFamily="{DynamicResource MonoFamily}"
+                 FontSize="11" Foreground="{DynamicResource TextDimBrush}"
+                 TextTrimming="CharacterEllipsis"
+                 IsVisible="{Binding WorktreePath, Converter={x:Static ObjectConverters.IsNotNull}}"/>
+      <!-- Row 3: branch line -->
+      <TextBlock Text="{Binding BranchLine}" FontFamily="{DynamicResource MonoFamily}"
+                 FontSize="11" Foreground="{DynamicResource TextDimBrush}"
+                 IsVisible="{Binding BranchLine, Converter={x:Static ObjectConverters.IsNotNull}}"/>
+      <!-- Button row -->
+      <StackPanel Orientation="Horizontal" Spacing="8" Margin="0,6,0,0">
+        <Button Classes="icon-btn" Content="Open diff"/>
+        <Button Classes="icon-btn" Content="Worktree"/>
+        <Button Classes="icon-btn" Content="Stop" Command="{Binding StopCommand}"/>
+        <Button Classes="icon-btn" Content="Approve &amp; merge" Command="{Binding ApproveMergeCommand}"/>
+      </StackPanel>
+    </StackPanel>
+  </Border>
+</UserControl>

src/ClaudeDo.Ui/Views/Islands/AgentStripView.axaml.cs

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

src/ClaudeDo.Ui/Views/Islands/DetailsIslandView.axaml

@@ -1,8 +1,34 @@
 <UserControl xmlns="https://github.com/avaloniaui"
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:vm="using:ClaudeDo.Ui.ViewModels.Islands"
+             xmlns:islands="using:ClaudeDo.Ui.Views.Islands"
              x:Class="ClaudeDo.Ui.Views.Islands.DetailsIslandView"
              x:DataType="vm:DetailsIslandViewModel">
-  <TextBlock Margin="14" Text="Details (placeholder)"
+  <ScrollViewer>
-             Foreground="{DynamicResource TextDimBrush}"/>
+    <StackPanel Margin="18,14" Spacing="14">
+      <!-- Editable title -->
+      <TextBox Text="{Binding EditableTitle, Mode=TwoWay}" FontSize="18"
+               BorderThickness="0" Background="Transparent"
+               Foreground="{DynamicResource TextBrush}"/>
+      <!-- Agent strip (only when a worktree exists or task is active) -->
+      <islands:AgentStripView/>
+      <!-- Session terminal: log + prompt -->
+      <islands:SessionTerminalView Height="260"/>
+      <!-- Subtasks -->
+      <ItemsControl ItemsSource="{Binding Subtasks}">
+        <ItemsControl.ItemTemplate>
+          <DataTemplate DataType="vm:SubtaskRowViewModel">
+            <StackPanel Orientation="Horizontal" Spacing="8" Margin="0,2">
+              <CheckBox IsChecked="{Binding Done, Mode=TwoWay}"/>
+              <TextBlock Text="{Binding Title}" VerticalAlignment="Center"
+                         Foreground="{DynamicResource TextBrush}"/>
+            </StackPanel>
+          </DataTemplate>
+        </ItemsControl.ItemTemplate>
+      </ItemsControl>
+      <!-- Notes -->
+      <TextBox Text="{Binding Notes, Mode=TwoWay}" AcceptsReturn="True"
+               TextWrapping="Wrap" MinHeight="80" PlaceholderText="Notes…"/>
+    </StackPanel>
+  </ScrollViewer>
 </UserControl>

src/ClaudeDo.Ui/Views/Islands/SessionTerminalView.axaml

@@ -21,9 +21,10 @@
       <ScrollViewer Name="LogScroll" VerticalScrollBarVisibility="Auto">
         <ItemsControl ItemsSource="{Binding Log}">
           <ItemsControl.ItemTemplate>
-            <DataTemplate x:CompileBindings="False" DataType="vm:LogLineViewModel">
+            <DataTemplate DataType="vm:LogLineViewModel">
-              <TextBlock Text="{Binding Text}" Classes="{Binding ClassName}"
+              <TextBlock Text="{Binding Text}" Tag="{Binding ClassName}"
                          FontFamily="{DynamicResource MonoFamily}" FontSize="11"
+                         Foreground="{DynamicResource TextDimBrush}"
                          TextWrapping="Wrap"/>
             </DataTemplate>
           </ItemsControl.ItemTemplate>

src/ClaudeDo.Ui/Views/Islands/SessionTerminalView.axaml.cs

@@ -0,0 +1,23 @@
+using System.Collections.Specialized;
+using Avalonia.Controls;
+using ClaudeDo.Ui.ViewModels.Islands;
+
+namespace ClaudeDo.Ui.Views.Islands;
+
+public partial class SessionTerminalView : UserControl
+{
+    public SessionTerminalView() { InitializeComponent(); }
+
+    protected override void OnDataContextChanged(EventArgs e)
+    {
+        base.OnDataContextChanged(e);
+        if (DataContext is DetailsIslandViewModel vm)
+            vm.Log.CollectionChanged += OnLogChanged;
+    }
+
+    private void OnLogChanged(object? sender, NotifyCollectionChangedEventArgs e)
+    {
+        if (e.Action == NotifyCollectionChangedAction.Add)
+            LogScroll.ScrollToEnd();
+    }
+}