made gui non-resizable

gui/src/main.qml

@@ -6,6 +6,11 @@ ApplicationWindow {
     visible: true
     width: 1280
     height: 720
+    maximumHeight: height
+    maximumWidth: width
+
+    minimumHeight: height
+    minimumWidth: width
     title: qsTr("Covert Channel - Control Panel")
 
     SwipeView {