Set power level from userdetaildialog

Add the option to set powerlevel to userdetaildialog.

This is done by making the powerleveldialog into it's own file and using that.

implements network/neochat#570

src/qml/Dialog/PowerLevelDialog.qml

@@ -0,0 +1,51 @@
+// SPDX-FileCopyrightText: 2023 James Graham <james.h.graham@protonmail.com>
+// SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
+
+import QtQuick 2.15
+import QtQuick.Controls 2.15 as QQC2
+import QtQuick.Layouts 1.15
+
+import org.kde.kirigami 2.15 as Kirigami
+
+import org.kde.neochat 1.0
+
+Kirigami.OverlaySheet {
+    id: root
+    title: i18n("Edit user power level")
+
+    property var room
+    property var userId
+    property int powerLevel
+
+    onSheetOpenChanged: {
+        if (sheetOpen) {
+            powerLevelComboBox.currentIndex = powerLevelComboBox.indexOfValue(root.powerLevel)
+        }
+    }
+    Kirigami.FormLayout {
+        QQC2.ComboBox {
+            id: powerLevelComboBox
+            model: ListModel {
+                id: powerLevelModel
+            }
+            textRole: "text"
+            valueRole: "powerLevel"
+            popup.z: root.z + 1 // Otherwise the popup will be behind the overlay sheet.
+
+            // Done this way so we can have translated strings.
+            Component.onCompleted: {
+                powerLevelModel.append({"text":  i18n("Member (0)"), "powerLevel": 0});
+                powerLevelModel.append({"text":  i18n("Moderator (50)"), "powerLevel": 50});
+                powerLevelModel.append({"text":  i18n("Admin (100)"), "powerLevel": 100});
+            }
+        }
+        QQC2.Button {
+            text: i18n("Confirm")
+            onClicked: {
+                room.setUserPowerLevel(root.userId, powerLevelComboBox.currentValue)
+                root.close()
+                root.destroy()
+            }
+        }
+    }
+}