feat(ui): interactive chat composer state on the session monitor VM

TaskMonitorViewModel gains IsInteractiveLive + ComposerDraft + SubmitComposer
(optimistic LogKind.User echo, then SendInteractiveMessageAsync) + StopInteractive,
driven by the InteractiveSessionStarted/Ended events. Since DetailsIslandViewModel
embeds this monitor, both task detail and Mission Control get the composer. Mission
Control auto-creates a monitor on InteractiveSessionStarted. Adds LogKind.User.

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

@@ -1,6 +1,6 @@
 namespace ClaudeDo.Ui.ViewModels.Islands;
 
-public enum LogKind { Sys, Tool, Claude, Stdout, Stderr, Done, Msg }
+public enum LogKind { Sys, Tool, Claude, Stdout, Stderr, Done, Msg, User }
 
 public sealed class LogLineViewModel
 {
@@ -16,6 +16,7 @@ public sealed class LogLineViewModel
         LogKind.Stderr => "err",
         LogKind.Done   => "done",
         LogKind.Msg    => "claude",
+        LogKind.User   => "you",
         _              => "",
     };
     public string ClassName => Kind switch
@@ -27,6 +28,7 @@ public sealed class LogLineViewModel
         LogKind.Stderr => "log-stderr",
         LogKind.Done   => "log-done",
         LogKind.Msg    => "log-msg",
+        LogKind.User   => "log-user",
         _              => "",
     };
 }

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

@@ -77,6 +77,17 @@ public sealed partial class TaskMonitorViewModel : ViewModelBase, IDisposable
     private readonly Action<string> _onTaskUpdated;
     private readonly Action<string, string, string> _onTaskQuestionAsked;
     private readonly Action<string, string> _onTaskQuestionResolved;
+    private readonly Action<string> _onInteractiveStarted;
+    private readonly Action<string> _onInteractiveEnded;
+
+    // Interactive composer — active while the worker is in an interactive session.
+    [ObservableProperty]
+    [NotifyCanExecuteChangedFor(nameof(SubmitComposerCommand))]
+    private bool _isInteractiveLive;
+
+    [ObservableProperty]
+    [NotifyCanExecuteChangedFor(nameof(SubmitComposerCommand))]
+    private string _composerDraft = string.Empty;
 
     // A question the running task raised via AskUser and is blocking on, plus the answer
     // the user is typing. Ephemeral (in-memory + live events) — the task is still Running.
@@ -144,6 +155,18 @@ public sealed partial class TaskMonitorViewModel : ViewModelBase, IDisposable
                 ClearPendingQuestion();
         };
         _worker.TaskQuestionResolvedEvent += _onTaskQuestionResolved;
+
+        _onInteractiveStarted = taskId =>
+        {
+            if (taskId == _subscribedTaskId) { IsInteractiveLive = true; AgentState = "running"; }
+        };
+        _worker.InteractiveSessionStartedEvent += _onInteractiveStarted;
+
+        _onInteractiveEnded = taskId =>
+        {
+            if (taskId == _subscribedTaskId) { IsInteractiveLive = false; AgentState = "done"; }
+        };
+        _worker.InteractiveSessionEndedEvent += _onInteractiveEnded;
     }
 
     // Surface a pending question (used by live event + re-attach hydration).
@@ -153,6 +176,33 @@ public sealed partial class TaskMonitorViewModel : ViewModelBase, IDisposable
         PendingQuestion = question;
     }
 
+    // Used by Mission Control when it creates the monitor after the started event already fired.
+    public void SetInteractiveLive(bool live)
+    {
+        IsInteractiveLive = live;
+        if (live) AgentState = "running";
+    }
+
+    [RelayCommand(CanExecute = nameof(CanSubmitComposer))]
+    private async System.Threading.Tasks.Task SubmitComposer()
+    {
+        if (string.IsNullOrEmpty(_subscribedTaskId)) return;
+        var text = ComposerDraft;
+        if (string.IsNullOrWhiteSpace(text)) return;
+        Log.Add(new LogLineViewModel { Kind = LogKind.User, Text = text });
+        ComposerDraft = string.Empty;
+        await _worker.SendInteractiveMessageAsync(_subscribedTaskId, text);
+    }
+
+    private bool CanSubmitComposer() => IsInteractiveLive && !string.IsNullOrWhiteSpace(ComposerDraft);
+
+    [RelayCommand]
+    private async System.Threading.Tasks.Task StopInteractive()
+    {
+        if (!string.IsNullOrEmpty(_subscribedTaskId) && IsInteractiveLive)
+            await _worker.StopInteractiveSessionAsync(_subscribedTaskId);
+    }
+
     private void ClearPendingQuestion()
     {
         PendingQuestionId = null;
@@ -201,6 +251,8 @@ public sealed partial class TaskMonitorViewModel : ViewModelBase, IDisposable
         SessionOutcome = null;
         Roadblocks = null;
         ClearPendingQuestion();
+        IsInteractiveLive = false;
+        ComposerDraft = string.Empty;
     }
 
     [ObservableProperty]
@@ -424,5 +476,7 @@ public sealed partial class TaskMonitorViewModel : ViewModelBase, IDisposable
         _worker.TaskUpdatedEvent  -= _onTaskUpdated;
         _worker.TaskQuestionAskedEvent    -= _onTaskQuestionAsked;
         _worker.TaskQuestionResolvedEvent -= _onTaskQuestionResolved;
+        _worker.InteractiveSessionStartedEvent -= _onInteractiveStarted;
+        _worker.InteractiveSessionEndedEvent   -= _onInteractiveEnded;
     }
 }

src/ClaudeDo.Ui/ViewModels/MissionControlViewModel.cs

@@ -19,6 +19,7 @@ public sealed partial class MissionControlViewModel : ViewModelBase, IDisposable
     private readonly Action<string, string, string, DateTime> _onTaskFinished;
     private readonly Action<string> _onTaskUpdated;
     private readonly Action _onConnectionRestored;
+    private readonly Action<string> _onInteractiveStarted;
 
     public ObservableCollection<TaskMonitorViewModel> Monitors { get; } = new();
 
@@ -67,6 +68,14 @@ public sealed partial class MissionControlViewModel : ViewModelBase, IDisposable
         _onConnectionRestored = () => { SeedActive(); _ = RefreshQueueAsync(); };
         _worker.ConnectionRestoredEvent += _onConnectionRestored;
 
+        _onInteractiveStarted = taskId =>
+        {
+            EnsureMonitor(taskId);
+            var m = Monitors.FirstOrDefault(x => x.SubscribedTaskId == taskId);
+            m?.SetInteractiveLive(true);
+        };
+        _worker.InteractiveSessionStartedEvent += _onInteractiveStarted;
+
         SeedActive();
         _ = RefreshQueueAsync();
     }
@@ -209,6 +218,7 @@ public sealed partial class MissionControlViewModel : ViewModelBase, IDisposable
         _worker.TaskFinishedEvent -= _onTaskFinished;
         _worker.TaskUpdatedEvent -= _onTaskUpdated;
         _worker.ConnectionRestoredEvent -= _onConnectionRestored;
+        _worker.InteractiveSessionStartedEvent -= _onInteractiveStarted;
         Monitors.CollectionChanged -= OnMonitorsChanged;
         foreach (var m in Monitors) m.Dispose();
         Monitors.Clear();