add squeekboard toggle button

modules/Bar.qml

@@ -59,6 +59,10 @@ PanelWindow {
                 Layout.fillHeight: true
             }
 
+            OskMenu {
+                Layout.fillHeight: true
+            }
+
             WifiMenu {
                 bar: bar
                 Layout.fillHeight: true

modules/OskMenu.qml

@@ -0,0 +1,32 @@
+import QtQuick
+import qs.config
+import qs.components
+import qs.services
+
+// Right section: the on-screen keyboard button. No menu behind it — a click
+// shows squeekboard, another hides it.
+Item {
+    id: root
+
+    // Machines with no squeekboard unit get no button at all.
+    visible: Osk.available
+
+    implicitWidth: button.implicitWidth
+
+    PanelButton {
+        id: button
+
+        anchors.verticalCenter: parent.verticalCenter
+        height: root.height - Theme.spacing
+        minContentWidth: Theme.iconSize
+        active: Osk.shown
+        activeColor: Theme.accent
+
+        onClicked: Osk.toggle()
+
+        KeyboardGlyph {
+            size: Theme.iconSize
+            color: button.active ? Theme.background : Theme.text
+        }
+    }
+}