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/MediaPopout.qml

@@ -172,7 +172,7 @@ Popout {
                 renderType: Text.NativeRendering
             }
 
-            P5Slider {
+            LevelSlider {
                 anchors.left: elapsed.right
                 anchors.right: total.left
                 anchors.leftMargin: Theme.padS