refactor(quickshell): drop the Persona names from the primitives

P5Panel, P5Button, P5Slider and P5Tooltip become Panel, ActionButton,
LevelSlider and Tooltip. ActionButton and LevelSlider avoid clashing
with QtQuick.Controls, which the ask panel imports.

quickshell/popouts/BatteryPopout.qml

@@ -123,7 +123,7 @@ Popout {
 
         // Follows the detail line rather than being pinned to the bottom of a
         // fixed-height panel, which is what left a dead band above it.
-        P5Button {
+        ActionButton {
             id: suspendButton
             anchors.top: detailText.bottom
             anchors.topMargin: Theme.padL