Move remaining code to app module

There's still some stuff that could potentially go elsewhere but I think it's enough for now.

src/app/qml/QrCodeMaximizeComponent.qml

@@ -0,0 +1,50 @@
+// SPDX-FileCopyrightText: 2023 Tobias Fella <tobias.fella@kde.org>
+// SPDX-License-Identifier: LGPL-2.0-or-later
+
+import QtQuick
+
+import org.kde.kirigamiaddons.labs.components as Components
+import org.kde.kirigami as Kirigami
+import org.kde.prison
+
+Components.AbstractMaximizeComponent {
+    id: root
+
+    required property string text
+    property color avatarColor
+    required property url avatarSource
+
+    onOpened: forceActiveFocus()
+
+    Shortcut {
+        sequences: [StandardKey.Cancel]
+        onActivated: root.close()
+    }
+
+    leading: Components.Avatar {
+        id: userAvatar
+        implicitWidth: Kirigami.Units.iconSizes.medium
+        implicitHeight: Kirigami.Units.iconSizes.medium
+
+        name: root.title
+        source: root.avatarSource
+        color: root.avatarColor
+    }
+
+    content: Item {
+        Keys.onEscapePressed: root.close()
+        Barcode {
+            barcodeType: Barcode.QRCode
+            content: root.text
+            height: Math.min(parent.height, Kirigami.Units.gridUnit * 20)
+            width: height
+            anchors.centerIn: parent
+        }
+        MouseArea {
+            id: closeArea
+            anchors.fill: parent
+            acceptedButtons: Qt.LeftButton
+            onClicked: root.close()
+        }
+    }
+}