add identity page for CertificateRequest status code

src/app/browser/window/tab/item/page/content/status/identity.rs

@@ -0,0 +1,29 @@
+use adw::StatusPage;
+use gtk::{prelude::ButtonExt, Align, Button};
+
+// Defaults
+const DEFAULT_ICON_NAME: &str = "avatar-default-symbolic";
+const DEFAULT_TITLE: &str = "Identity";
+const DEFAULT_DESCRIPTION: &str = "Client certificate required to continue!";
+const DEFAULT_BUTTON_LABEL: &str = "Select";
+
+/// Create new default preset for `Identity`
+/// [StatusPage](https://gnome.pages.gitlab.gnome.org/libadwaita/doc/main/class.StatusPage.html)
+pub fn new_gobject() -> StatusPage {
+    // Init certificate selection
+    let button = &Button::builder()
+        .label(DEFAULT_BUTTON_LABEL)
+        .halign(Align::Center)
+        .build();
+
+    // Init events
+    button.connect_activate(|_| {}); // @TODO
+
+    // Init status page
+    StatusPage::builder()
+        .description(DEFAULT_DESCRIPTION)
+        .icon_name(DEFAULT_ICON_NAME)
+        .title(DEFAULT_TITLE)
+        .child(button)
+        .build()
+}