feat(ui): detach a monitor into its own window

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

@@ -142,6 +142,12 @@ public sealed partial class TaskMonitorViewModel : ViewModelBase, IDisposable
     // Set by the host (e.g. Mission Control) to navigate the main app to this task.
     public Action<string>? OpenInAppRequested { get; set; }
 
+    // Set by the host (Mission Control) to pop this monitor out into its own window.
+    public Action<TaskMonitorViewModel>? DetachRequested { get; set; }
+
+    [RelayCommand]
+    private void Detach() => DetachRequested?.Invoke(this);
+
     [RelayCommand]
     private void OpenInApp()
     {

src/ClaudeDo.Ui/ViewModels/IslandsShellViewModel.cs

@@ -213,6 +213,7 @@ public sealed partial class IslandsShellViewModel : ViewModelBase, IDisposable
         Lists = lists; Tasks = tasks; Details = details; Worker = worker;
         MissionControl = missionControl;
         MissionControl.OpenInApp = id => _ = RevealTaskAsync(id);
+        MissionControl.ShowDetached = (monitor, reDock) => Dialogs?.ShowDetachedMonitor(monitor, reDock);
         _updateCheck = updateCheck;
         _installerLocator = installerLocator;
         _workerLocator = workerLocator;

src/ClaudeDo.Ui/ViewModels/MissionControlViewModel.cs

@@ -33,6 +33,10 @@ public sealed partial class MissionControlViewModel : ViewModelBase, IDisposable
         }
     }
 
+    // View-layer seam: show a detached monitor in its own window. Second arg is the re-dock callback
+    // invoked when that window closes.
+    public Action<TaskMonitorViewModel, Action>? ShowDetached { get; set; }
+
     public bool HasMonitors => Monitors.Count > 0;
 
     public MissionControlViewModel(IDbContextFactory<ClaudeDoDbContext> dbFactory, IWorkerClient worker)
@@ -65,10 +69,24 @@ public sealed partial class MissionControlViewModel : ViewModelBase, IDisposable
         var monitor = new TaskMonitorViewModel(_dbFactory, _worker);
         monitor.SetTaskId(taskId);
         monitor.OpenInAppRequested = _openInApp;
+        monitor.DetachRequested = Detach;
         Monitors.Add(monitor);
         _ = HydrateAsync(monitor, taskId);
     }
 
+    private void Detach(TaskMonitorViewModel monitor)
+    {
+        if (!Monitors.Contains(monitor)) return;
+        Monitors.Remove(monitor);            // drop from grid — do NOT dispose; it keeps streaming
+        ShowDetached?.Invoke(monitor, () => ReDock(monitor));
+    }
+
+    private void ReDock(TaskMonitorViewModel monitor)
+    {
+        if (!Monitors.Contains(monitor) && monitor.SubscribedTaskId is not null)
+            Monitors.Add(monitor);           // back into the grid
+    }
+
     private async System.Threading.Tasks.Task HydrateAsync(TaskMonitorViewModel monitor, string taskId)
     {
         try