Create Cross-signing keys when required

This should be almost entirely in libquotient, but that's not prepared to actually use user-interactive authentication...

src/qml/CrossSigningSetupDialog.qml

@@ -0,0 +1,33 @@
+// SPDX-FileCopyrightText: 2024 Tobias Fella <tobias.fella@kde.org>
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+import QtQuick
+import QtQuick.Controls as QQC2
+import org.kde.kirigami as Kirigami
+
+import org.kde.neochat
+
+Kirigami.PromptDialog {
+    id: root
+
+    required property NeoChatConnection connection
+
+    title: i18nc("@title:dialog", "Setup Encryption Keys")
+    dialogType: Kirigami.PromptDialog.Information
+
+    onRejected: {
+        root.close();
+    }
+
+    footer: QQC2.DialogButtonBox {
+        standardButtons: QQC2.Dialog.Cancel
+
+        QQC2.Button {
+            text: i18nc("@action:button", "Setup Keys")
+            QQC2.DialogButtonBox.buttonRole: QQC2.DialogButtonBox.AcceptRole
+            onClicked: {
+                root.connection.setupCrossSigningKeys("password123");
+            }
+        }
+    }
+}

src/qml/Main.qml

@@ -309,6 +309,12 @@ Kirigami.ApplicationWindow {
                 url: url
             }).open();
         }
+
+        function onCrossSigningSetupRequired() {
+            Qt.createComponent("org.kde.neochat", "CrossSigningSetupDialog").createObject(this, {
+                connection: root.connection
+            }).open();
+        }
     }
 
     HoverLinkIndicator {