Fix: Remote Desktop — 60fps, Screen-Wechsel live, Consent-Dialog sichtbar (v2.3.0)

- CaptureModeRunner: Thread.Sleep(150) → 16ms (~60fps) + Skip-if-unchanged via Pixel-Hash
- RtcService: rdp_switch_screen Handler — Screen wechseln ohne Consent-Dialog
- RtcService: Fallback bei Consent-Fehler → rdp_denied statt silent capture
- RdpConsentWindow: WindowStyle=ToolWindow + ShowInTaskbar=True (jetzt in Taskleiste sichtbar)
- RemoteDesktopPanel: Screen-Dropdown auch während aktiver Verbindung nutzbar
- Version: 2.2.0 → 2.3.0

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

agent-cs/UI/RdpConsentWindow.xaml

@@ -1,15 +1,16 @@
 <Window x:Class="ITNexusAgent.UI.RdpConsentWindow"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        Title="IT Nexus – Bildschirmzugriff"
+        Title="IT Nexus – Bildschirmzugriff angefordert"
         Width="480" Height="Auto"
         SizeToContent="Height"
         WindowStartupLocation="CenterScreen"
         ResizeMode="NoResize"
-        WindowStyle="None"
+        WindowStyle="ToolWindow"
         AllowsTransparency="False"
         Background="#1A1D2E"
         Topmost="True"
+        ShowInTaskbar="True"
         FontFamily="Segoe UI">
 
     <Window.Resources>