Bar widgets: modular loading refactoring via BarWidgetRegistry+NWidgetLoader

- Hot reload is working again.
- Should also be more memory efficient on multi monitors.

Widgets/NWidgetLoader.qml

@@ -0,0 +1,46 @@
+import QtQuick
+import Quickshell
+import qs.Services
+
+Item {
+  id: root
+
+  property string widgetName: ""
+  property var widgetProps: ({})
+  property bool enabled: true
+
+  // Don't reserve space unless the loaded widget is really visible
+  implicitWidth: loader.item ? loader.item.visible ? loader.item.implicitWidth : 0 : 0
+  implicitHeight: loader.item ? loader.item.visible ? loader.item.implicitHeight : 0 : 0
+
+  Loader {
+    id: loader
+
+    anchors.fill: parent
+    active: enabled && widgetName !== ""
+    sourceComponent: {
+      if (!active) {
+        return null
+      }
+      return BarWidgetRegistry.getWidget(widgetName)
+    }
+
+    onLoaded: {
+      if (item && widgetProps) {
+        // Apply properties to loaded widget
+        for (var prop in widgetProps) {
+          if (item.hasOwnProperty(prop)) {
+            item[prop] = widgetProps[prop]
+          }
+        }
+      }
+    }
+  }
+
+  // Error handling
+  onWidgetNameChanged: {
+    if (widgetName && !BarWidgetRegistry.hasWidget(widgetName)) {
+      Logger.warn("WidgetLoader", "Widget not found in registry:", widgetName)
+    }
+  }
+}