Add RustDesk Flatpak installation to autoinstaller

- Added Flatpak installation of RustDesk in setup-installed-system.sh
- Includes Flathub remote setup and non-interactive installation
- Runs before final system configuration completion

config/includes.binary/setup-installed-system.sh

@@ -120,6 +120,18 @@ elif [ -d "$TARGET_MOUNT/etc/init.d" ]; then
 fi
 echo "SSH service enabled on installed system"
 
+# 9. Install RustDesk via Flatpak
+echo "Installing RustDesk via Flatpak..."
+if [ -x "$TARGET_MOUNT/usr/bin/flatpak" ] && [ -f "$TARGET_MOUNT/root/com.rustdesk.RustDesk.flatpakref" ]; then
+    # Add Flathub remote if not already added
+    chroot "$TARGET_MOUNT" flatpak remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo 2>/dev/null || true
+    # Install RustDesk
+    chroot "$TARGET_MOUNT" flatpak install -y --noninteractive /root/com.rustdesk.RustDesk.flatpakref
+    echo "RustDesk installed successfully via Flatpak"
+else
+    echo "Warning: Flatpak not available or RustDesk flatpakref not found"
+fi
+
 echo "Installed system configuration completed!"
 echo ""
 echo "Installed system will now:"