Address momus review: fix icons, vertical layout, popup coordination

- Replace nerd font glyphs that were stripped during the initial widget
  writes with verified codepoints sourced from the JetBrains Mono Nerd
  Font cmap (cpu-64-bit, scale-balance, notification-clear-all, etc).
- systemStats now switches to a Column layout when the bar is vertical
  so the widget no longer overflows a 28px-wide side bar.
- Remove notificationCenter from defaults: it registers a notification
  server and would collide with the mako daemon Omarchy autostarts.
- PopupCard owns the popout coordinator lifecycle and delegates close to
  its widget owner when provided; calendar and media now pass owner.
- brightness debounces brightnessctl writes through a coalescing timer
  to avoid spawning a process per slider tick.
- audioPanel tracks unfiltered Pipewire sinks/streams via PwObjectTracker
  so audio metadata becomes available before filtering.
- ModuleSlot re-injects bar/moduleName/settings whenever the bar config
  serial changes so widget settings update live with bar.json.
- Guard null bar references in workspacesPro and systemStats components
  that are constructed before bar injection.

default/quickshell/bar/common/PopupCard.qml

@@ -11,13 +11,13 @@ PopupWindow {
   property int padding: 14
   property int contentWidth: 280
   property int contentHeight: 200
-  property bool dismissOnOutsideClick: true
   property bool open: false
 
-  onOpenChanged: {
-    if (!bar) return
-    if (open) bar.requestPopout(owner || root)
-    else if (bar.activePopout === (owner || root)) bar.releasePopout(owner || root)
+  readonly property var coordinatorKey: owner || root
+
+  function closePopout() {
+    if (owner && "closePopout" in owner) owner.closePopout()
+    else root.open = false
   }
 
   default property alias contentItem: contentHolder.children
@@ -27,6 +27,12 @@ PopupWindow {
   implicitWidth: contentWidth
   implicitHeight: contentHeight
 
+  onOpenChanged: {
+    if (!bar) return
+    if (open) bar.requestPopout(coordinatorKey)
+    else if (bar.activePopout === coordinatorKey) bar.releasePopout(coordinatorKey)
+  }
+
   anchor {
     id: popupAnchor
     window: anchorItem ? anchorItem.QsWindow.window : null
@@ -71,7 +77,7 @@ PopupWindow {
     border.color: root.bar ? root.bar.foreground : "#cacccc"
     border.width: 1
     radius: 0
-    opacity: root.open ? 0.97 : 0
+    opacity: root.open ? 0.98 : 0
 
     Behavior on opacity {
       NumberAnimation { duration: 140; easing.type: Easing.OutCubic }
@@ -82,12 +88,5 @@ PopupWindow {
       anchors.fill: parent
       anchors.margins: root.padding
     }
-
-    MouseArea {
-      anchors.fill: parent
-      acceptedButtons: Qt.NoButton
-      hoverEnabled: false
-      propagateComposedEvents: true
-    }
   }
 }