put shell in subdir, and add nix package

shell/bar/mpris/Button.qml

@@ -0,0 +1,42 @@
+import QtQuick
+import "../../mpris" as Mpris
+import "../../widgets" as Widgets
+import "../.."
+
+Widgets.MaterialButton {
+    id: root
+    radius: 6
+    implicitWidth: mediaInfo.contentWidth + 8
+    implicitHeight: parent.height
+    // onClicked: {
+    //     popup.visible = !popup.visible;
+    // }
+
+    required property var bar
+    property var player: Mpris.Controller.trackedPlayer
+
+    Text {
+        id: mediaInfo
+        text: root.player?.trackTitle ?? ""
+        color: root.containsMouse ? ShellSettings.colors["inverse_primary"] : ShellSettings.colors["inverse_surface"]
+        elide: Text.ElideRight
+        horizontalAlignment: Text.AlignHCenter
+        verticalAlignment: Text.AlignVCenter
+        font.pointSize: 11
+        anchors.centerIn: parent
+
+        Behavior on color {
+            ColorAnimation {
+                duration: 200
+            }
+        }
+    }
+}
+
+// WidgetWindow {
+//     id: popup
+//     visible: false
+//     parentWindow: root.bar
+//
+//     // anchor.window: root.bar
+// }

shell/bar/mpris/WidgetWindow.qml

@@ -0,0 +1,9 @@
+import Quickshell
+
+PopupWindow {
+    id: root
+    color: "red"
+    implicitWidth: 500
+    implicitHeight: 500
+
+}