💄 Añade componente PoweredBy para copyright

Adapta la página de bienvenida al tratamiento revisado de regiones y
añade en el pie el componente `PoweredBy` para la nota de copyright.

tests/component_poweredby.rs

@@ -0,0 +1,100 @@
+use pagetop::prelude::*;
+
+#[pagetop::test]
+async fn poweredby_default_shows_only_pagetop_recognition() {
+    let _app = service::test::init_service(Application::new().test()).await;
+
+    let p = PoweredBy::default();
+    let html = render_component(&p);
+
+    // Debe mostrar el bloque de reconocimiento a PageTop.
+    assert!(html.contains("poweredby__pagetop"));
+
+    // Y NO debe mostrar el bloque de copyright.
+    assert!(!html.contains("poweredby__copyright"));
+}
+
+#[pagetop::test]
+async fn poweredby_new_includes_current_year_and_app_name() {
+    let _app = service::test::init_service(Application::new().test()).await;
+
+    let p = PoweredBy::new();
+    let html = render_component(&p);
+
+    let year = Utc::now().format("%Y").to_string();
+    assert!(html.contains(&year), "HTML should include the current year");
+
+    // El nombre de la app proviene de `global::SETTINGS.app.name`.
+    let app_name = &global::SETTINGS.app.name;
+    assert!(
+        html.contains(app_name),
+        "HTML should include the application name"
+    );
+
+    // Debe existir el span de copyright.
+    assert!(html.contains("poweredby__copyright"));
+}
+
+#[pagetop::test]
+async fn poweredby_with_copyright_overrides_text() {
+    let _app = service::test::init_service(Application::new().test()).await;
+
+    let custom = "2001 © FooBar Inc.";
+    let p = PoweredBy::default().with_copyright(Some(custom));
+    let html = render_component(&p);
+
+    assert!(html.contains(custom));
+    assert!(html.contains("poweredby__copyright"));
+}
+
+#[pagetop::test]
+async fn poweredby_with_copyright_none_hides_text() {
+    let _app = service::test::init_service(Application::new().test()).await;
+
+    let p = PoweredBy::new().with_copyright(None::<String>);
+    let html = render_component(&p);
+
+    assert!(!html.contains("poweredby__copyright"));
+    // El reconocimiento a PageTop siempre debe aparecer.
+    assert!(html.contains("poweredby__pagetop"));
+}
+
+#[pagetop::test]
+async fn poweredby_link_points_to_crates_io() {
+    let _app = service::test::init_service(Application::new().test()).await;
+
+    let p = PoweredBy::default();
+    let html = render_component(&p);
+
+    assert!(
+        html.contains("https://crates.io/crates/pagetop"),
+        "Link should point to crates.io/pagetop"
+    );
+}
+
+#[pagetop::test]
+async fn poweredby_getter_reflects_internal_state() {
+    let _app = service::test::init_service(Application::new().test()).await;
+
+    // Por defecto no hay copyright.
+    let p0 = PoweredBy::default();
+    assert_eq!(p0.copyright(), None);
+
+    // Y `new()` lo inicializa con año + nombre de app.
+    let p1 = PoweredBy::new();
+    let c1 = p1.copyright().expect("Expected copyright to exis");
+    assert!(c1.contains(&Utc::now().format("%Y").to_string()));
+    assert!(c1.contains(&global::SETTINGS.app.name));
+}
+
+// HELPERS *****************************************************************************************
+
+fn render(x: &impl Render) -> String {
+    x.render().into_string()
+}
+
+fn render_component<C: Component>(c: &C) -> String {
+    let mut cx = Context::default();
+    let pm = c.prepare_component(&mut cx);
+    render(&pm)
+}