Add a no-animations mode, on by default in VMs (#13550)

A machine without a GPU, like most VMs, renders through llvmpipe on the
CPU, where every animated frame and every translucent window costs. In a
VM, opening and closing a terminal took ~5s of CPU; a panel ~3.4s.

omarchy toggle animations (also under Toggle > Animations) places a Hyprland
flag that turns off animations, blur and shadows and makes windows opaque.
The shell follows Hyprland's animations:enabled, rereading it on every
config reload: its one-shot animations run for Style.duration(ms), which
is then 0, and its spinners, pulses and title marquee hold still. A new
install in a VM starts with the flag in place.

Measured in the ISO test VM (llvmpipe), CPU per interaction:
terminal open+close 5000ms -> 481ms, workspace switch 1670ms -> 409ms,
audio panel 3446ms -> 796ms, volume OSD 2324ms -> 584ms, menu 2028ms ->
1241ms.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

shell/plugins/bar/Bar.qml

@@ -80,9 +80,9 @@ Item {
   property color background: Color.bar.background
   property color urgent: Color.bar.active
 
-  Behavior on barForeground { enabled: root.foregroundAnimationEnabled; ColorAnimation { duration: 420; easing.type: Easing.InOutCubic } }
-  Behavior on background { ColorAnimation { duration: 420; easing.type: Easing.InOutCubic } }
-  Behavior on urgent { ColorAnimation { duration: 420; easing.type: Easing.InOutCubic } }
+  Behavior on barForeground { enabled: root.foregroundAnimationEnabled; ColorAnimation { duration: Style.duration(420); easing.type: Easing.InOutCubic } }
+  Behavior on background { ColorAnimation { duration: Style.duration(420); easing.type: Easing.InOutCubic } }
+  Behavior on urgent { ColorAnimation { duration: Style.duration(420); easing.type: Easing.InOutCubic } }
   property var tooltipTarget: null
   property var pendingTooltipTarget: null
   property string tooltipText: ""
@@ -1509,7 +1509,7 @@ Item {
         opacity: root.barMoveCandidate === modelData ? (root.transparent ? 0.45 : 0.7) : 0
 
         Behavior on opacity {
-          NumberAnimation { duration: 140; easing.type: Easing.OutCubic }
+          NumberAnimation { duration: Style.duration(140); easing.type: Easing.OutCubic }
         }
       }
     }
@@ -1895,7 +1895,7 @@ Item {
       z: 50
 
       Behavior on opacity {
-        NumberAnimation { duration: 120; easing.type: Easing.OutCubic }
+        NumberAnimation { duration: Style.duration(120); easing.type: Easing.OutCubic }
       }
     }
 

shell/plugins/bar/widgets/ActiveWindow.qml

@@ -18,7 +18,7 @@ BarWidget {
   implicitHeight: barSize
 
   Behavior on implicitWidth {
-    NumberAnimation { duration: 180; easing.type: Easing.OutCubic }
+    NumberAnimation { duration: Style.duration(180); easing.type: Easing.OutCubic }
   }
 
   Item {

shell/plugins/bar/widgets/Tray.qml

@@ -216,7 +216,7 @@ BarWidget {
   implicitHeight: root.vertical ? trayContent.implicitHeight : root.barSize
 
   Behavior on revealProgress {
-    NumberAnimation { duration: root.animationDuration; easing.type: Easing.OutCubic }
+    NumberAnimation { duration: Style.duration(root.animationDuration); easing.type: Easing.OutCubic }
   }
 
   Loader {