feat(power): add power profile component

modules/bar/PowerProfileWidget.qml

@@ -0,0 +1,11 @@
+pragma ComponentBehavior: Bound
+
+import qs.ui
+import qs.services
+
+BarButton {
+  hoverHighlight: false
+  pointerCursor: false
+  label: PowerProfile.name
+  iconSource: PowerProfile.icon
+}