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/PopoutSurface.qml

@@ -3,8 +3,8 @@ import "root:/config"
 import "root:/components"
 
 // The slab every popout sits on. Pure preset — it declares no children of its
-// own, so P5Panel's default content property stays usable by callers.
-P5Panel {
+// own, so Panel's default content property stays usable by callers.
+Panel {
     property color tone: Theme.primary
     property bool textured: false
 
@@ -14,7 +14,7 @@ P5Panel {
     readonly property bool attached: parent?.frameAttached ?? false
 
     fill: attached ? "transparent" : Theme.mantle
-    // Zero, not a transparent fill: P5Panel re-applies this opacity to the
+    // Zero, not a transparent fill: Panel re-applies this opacity to the
     // fill colour, which turned "transparent" into 97% black.
     fillOpacity: attached ? 0 : 0.97
     // The frame is structure: a neutral hairline. A free-standing panel takes