style: one sans and one mono, and no stretched text

GTK, Qt and Hyprland's own text move to the shell's pair: Noto Sans for
interface text and JetBrainsMono Nerd Font for figures and code. They
had been Adwaita Sans, Sans Serif and FiraCode.

The tray menu now slides and fades in without scaling, and a pressed
button sinks one pixel instead of shrinking, so no label is ever
stretched mid-animation.

quickshell/components/P5Button.qml

@@ -142,8 +142,11 @@ FocusScope {
         }
     }
 
+    // A press sinks the button one whole pixel instead of shrinking it, so
+    // its label stays on the pixel grid.
     transform: Translate {
         x: root.pressed ? 0 : (root.highlighted ? root.lunge : 0)
+        y: root.pressed ? 1 : 0
 
         Behavior on x {
             NumberAnimation {
@@ -153,10 +156,6 @@ FocusScope {
         }
     }
 
-    scale: root.pressed ? 0.97 : 1.0
-    Behavior on scale {
-        NumberAnimation { duration: Theme.durFast; easing.type: Easing.OutExpo }
-    }
 
     HoverHandler {
         id: hover