bar: fix storing only one

modules/bar/Content.qml

@@ -19,7 +19,7 @@ StyledRect {
 
     color: BorderConfig.colour
 
-    Component.onCompleted: Visibilities.bar = this
+    Component.onCompleted: Visibilities.bars[screen] = this
 
     Item {
         id: child

modules/drawers/Drawers.qml

@@ -43,7 +43,7 @@ Variants {
             anchors.left: true
             anchors.right: true
 
-            margins.left: Visibilities.bar?.implicitWidth ?? 0
+            margins.left: Visibilities.bars[screen]?.implicitWidth ?? 0
 
             Variants {
                 id: regions

services/Visibilities.qml

@@ -4,8 +4,7 @@ import Quickshell
 
 Singleton {
     property var screens: ({})
-
-    property var bar
+    property var bars: ({})
 
     function getForActive(): PersistentProperties {
         return Object.entries(screens).find(s => s[0].slice(s[0].indexOf('"') + 1, s[0].lastIndexOf('"')) === Hyprland.focusedMonitor.name)[1];