feat(daily-prep): add live prep-output mode to the Details island

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

src/ClaudeDo.Localization/locales/de.json

@@ -138,7 +138,8 @@
     "toggleEditPreviewTip": "Bearbeiten/Vorschau umschalten",
     "previewBtn": "Vorschau",
     "editBtn": "Bearbeiten",
-    "descriptionPlaceholder": "Aufgabendetails hinzufügen (Markdown unterstützt)..."
+    "descriptionPlaceholder": "Aufgabendetails hinzufügen (Markdown unterstützt)...",
+    "prepTitle": "Tagesvorbereitung"
   },
   "agent": {
     "stopTip": "Agent stoppen",

src/ClaudeDo.Localization/locales/en.json

@@ -138,7 +138,8 @@
     "toggleEditPreviewTip": "Toggle edit/preview",
     "previewBtn": "Preview",
     "editBtn": "Edit",
-    "descriptionPlaceholder": "Add task details (markdown supported)..."
+    "descriptionPlaceholder": "Add task details (markdown supported)...",
+    "prepTitle": "Daily prep"
   },
   "agent": {
     "stopTip": "Stop agent",

src/ClaudeDo.Ui/ViewModels/Islands/DetailsIslandViewModel.cs

@@ -54,6 +54,14 @@ public sealed partial class DetailsIslandViewModel : ViewModelBase
     private readonly INotesApi _notesApi;
 
     [ObservableProperty] private bool _isNotesMode;
+    [ObservableProperty] private bool _isPrepMode;
+    [ObservableProperty] private bool _isPrepRunning;
+    public ObservableCollection<LogLineViewModel> PrepLog { get; } = new();
+    public bool IsTaskDetailVisible => !IsNotesMode && !IsPrepMode;
+
+    partial void OnIsNotesModeChanged(bool value) => OnPropertyChanged(nameof(IsTaskDetailVisible));
+    partial void OnIsPrepModeChanged(bool value) => OnPropertyChanged(nameof(IsTaskDetailVisible));
+
     public NotesEditorViewModel Notes { get; private set; } = null!;
 
     // Current task row (set by IslandsShellViewModel via Bind)
@@ -207,6 +215,7 @@ public sealed partial class DetailsIslandViewModel : ViewModelBase
     // Claude CLI stream-json parser + buffer for partial text deltas
     private readonly StreamLineFormatter _formatter = new();
     private readonly StringBuilder _claudeBuf = new();
+    private readonly StringBuilder _prepClaudeBuf = new();
 
     // The task ID we are currently subscribed to for live log messages
     private string? _subscribedTaskId;
@@ -285,6 +294,9 @@ public sealed partial class DetailsIslandViewModel : ViewModelBase
 
         // Subscribe once; filter by current task id inside the handler
         _worker.TaskMessageEvent += OnTaskMessage;
+        _worker.PrepStartedEvent  += OnPrepStarted;
+        _worker.PrepLineEvent     += OnPrepLine;
+        _worker.PrepFinishedEvent += OnPrepFinished;
 
         // Re-evaluate CanExecute when worker connection flips.
         _worker.PropertyChanged += (_, e) =>
@@ -345,9 +357,7 @@ public sealed partial class DetailsIslandViewModel : ViewModelBase
         if (line.StartsWith("[stdout]", StringComparison.OrdinalIgnoreCase))
         {
             var body = line["[stdout]".Length..].TrimStart();
-            var formatted = _formatter.FormatLine(body);
-            if (formatted is null) return; // filter noise (message_start, etc.)
-            AppendClaudeText(formatted);
+            AppendStdoutLine(Log, body);
             return;
         }
 
@@ -363,20 +373,40 @@ public sealed partial class DetailsIslandViewModel : ViewModelBase
         Log.Add(new LogLineViewModel { Kind = kind, Text = line });
     }
 
-    private void AppendClaudeText(string chunk)
+    private void AppendStdoutLine(ObservableCollection<LogLineViewModel> target, string line)
     {
-        _claudeBuf.Append(chunk);
+        var formatted = _formatter.FormatLine(line);
+        if (formatted is null) return;
+        var buf = ReferenceEquals(target, Log) ? _claudeBuf : _prepClaudeBuf;
+        AppendClaudeText(formatted, target, buf);
+    }
+
+    private void OnPrepStarted()
+    {
+        PrepLog.Clear();
+        IsPrepRunning = true;
+    }
+
+    private void OnPrepLine(string line) => AppendStdoutLine(PrepLog, line);
+
+    private void OnPrepFinished(bool success) => IsPrepRunning = false;
+
+    private void AppendClaudeText(string chunk) => AppendClaudeText(chunk, Log, _claudeBuf);
+
+    private static void AppendClaudeText(string chunk, ObservableCollection<LogLineViewModel> target, StringBuilder buf)
+    {
+        buf.Append(chunk);
         // Emit a log entry for every completed line; keep the trailing remainder buffered.
         while (true)
         {
-            var text = _claudeBuf.ToString();
+            var text = buf.ToString();
             var nl = text.IndexOf('\n');
             if (nl < 0) break;
             var piece = text[..nl].TrimEnd('\r');
             if (!string.IsNullOrWhiteSpace(piece))
-                Log.Add(new LogLineViewModel { Kind = LogKind.Claude, Text = piece });
-            _claudeBuf.Clear();
-            _claudeBuf.Append(text[(nl + 1)..]);
+                target.Add(new LogLineViewModel { Kind = LogKind.Claude, Text = piece });
+            buf.Clear();
+            buf.Append(text[(nl + 1)..]);
         }
     }
 
@@ -478,13 +508,22 @@ public sealed partial class DetailsIslandViewModel : ViewModelBase
     public void ShowNotes()
     {
         Bind(null);
+        IsPrepMode = false;
         IsNotesMode = true;
         _ = Notes.LoadDayAsync(DateOnly.FromDateTime(DateTime.Today));
     }
 
+    public void ShowPrep()
+    {
+        Bind(null);
+        IsNotesMode = false;
+        IsPrepMode = true;
+    }
+
     public void Bind(TaskRowViewModel? row)
     {
         IsNotesMode = false;
+        IsPrepMode = false;
         _loadCts?.Cancel();
         _loadCts?.Dispose();
         _loadCts = new CancellationTokenSource();

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

@@ -127,10 +127,10 @@
     <!-- ── Agent status strip (sticky, above metadata footer) ── -->
     <islands:AgentStripView DockPanel.Dock="Bottom"/>
 
-    <!-- ── Body: task details (normal) or notes editor (notes mode) ── -->
+    <!-- ── Body: task details (normal), notes editor (notes mode), or prep log (prep mode) ── -->
     <Grid>
     <ScrollViewer VerticalScrollBarVisibility="Auto"
-                  IsVisible="{Binding !IsNotesMode}">
+                  IsVisible="{Binding IsTaskDetailVisible}">
       <StackPanel Spacing="0">
 
         <!-- Planning merge section — visible only for planning parent tasks -->
@@ -299,6 +299,29 @@
     <Panel IsVisible="{Binding IsNotesMode}">
       <islands:NotesEditorView DataContext="{Binding Notes}"/>
     </Panel>
+    <Panel IsVisible="{Binding IsPrepMode}">
+      <DockPanel>
+        <TextBlock DockPanel.Dock="Top" Margin="16,12"
+                   Text="{loc:Tr details.prepTitle}" Classes="h2"/>
+        <ScrollViewer>
+          <ItemsControl ItemsSource="{Binding PrepLog}">
+            <ItemsControl.ItemTemplate>
+              <DataTemplate DataType="vm:LogLineViewModel">
+                <Grid ColumnDefinitions="60,*" Margin="0,1">
+                  <TextBlock Grid.Column="0"
+                             Classes="log-ts"
+                             Text="{Binding TimestampFormatted}"/>
+                  <SelectableTextBlock Grid.Column="1"
+                                       Text="{Binding Text}" Tag="{Binding ClassName}"
+                                       Foreground="{DynamicResource TextDimBrush}"
+                                       TextWrapping="Wrap"/>
+                </Grid>
+              </DataTemplate>
+            </ItemsControl.ItemTemplate>
+          </ItemsControl>
+        </ScrollViewer>
+      </DockPanel>
+    </Panel>
     </Grid>
 
   </DockPanel>