feat(ui): reveal a task by id from anywhere

tests/ClaudeDo.Ui.Tests/ViewModels/MissionControlViewModelTests.cs

@@ -114,4 +114,20 @@ public class MissionControlViewModelTests : IDisposable
         public override IReadOnlyList<ActiveTask> GetActiveTasks()
             => new[] { new ActiveTask("slot-1", "seed1", DateTime.UtcNow) };
     }
+
+    [Fact]
+    public void OpenInApp_PropagatesToMonitors_AndCommandInvokesHook()
+    {
+        var worker = new FakeWorker();
+        using var vm = BuildVm(worker);
+
+        string? revealed = null;
+        vm.OpenInApp = id => revealed = id;
+
+        worker.RaiseTaskStarted("slot-1", "t1", DateTime.UtcNow);
+
+        vm.Monitors[0].OpenInAppCommand.Execute(null);
+
+        Assert.Equal("t1", revealed);
+    }
 }