move ui lifetime to a manager for better lifetime control

Torch.Server/Managers/UiManager.cs

@@ -0,0 +1,37 @@
+using System.Threading;
+using System.Windows.Threading;
+using JetBrains.Annotations;
+using Torch.Managers;
+
+namespace Torch.Server.Managers;
+
+public class UiManager(TorchServer torchInstance) : Manager(torchInstance)
+{
+    [CanBeNull] private Thread _uiThread;
+    [CanBeNull] private Dispatcher _dispatcher;
+
+    public override void Attach()
+    {
+        _uiThread = new Thread(() =>
+        {
+            var ui = new TorchUI(torchInstance);
+
+            _dispatcher = Dispatcher.CurrentDispatcher;
+                
+            SynchronizationContext.SetSynchronizationContext(
+                new DispatcherSynchronizationContext(_dispatcher));
+
+            ui.ShowDialog();
+        });
+
+        _uiThread.SetApartmentState(ApartmentState.STA);
+        _uiThread.Start();
+    }
+
+    public override void Detach()
+    {
+        _dispatcher?.InvokeShutdown();
+        if (Thread.CurrentThread != _uiThread)
+            _uiThread?.Join();
+    }
+}