fix(paises,buscar): tappable ISO rows and a reconnect card

Item 24 / audit 5.1-5.3, 5.5 (t4:255-269): Paises' "Tus idiomas" was
a Wrap of non-interactive Chips, and the full list was a plain
ListTile with no ISO column and no onTap. Both now share one tappable
row (ISO code, name, station count, chevron); the first "Tus idiomas"
row gets the prototype's teal-tinted highlight. The one production
call site wires the tap to filter Buscar by that country's code and
pop back -- EstadoBusqueda.buscar(pais: ...) already accepts any ISO
alpha-2 code, not just the ~10 presets in the filter sheet.

Item 25 / audit 13.2 (t4:643-646): a reconnect card (rotating ring,
station name, "Reconectando...", a stop affordance) replaces the
complete absence of any reconnect signal outside a word in the mini
player. Ships WITHOUT the prototype's attempt counter: the only live
ControladorReconexion instance is a private field of
PluriWaveAudioHandler inside servicio_audio.dart, a file this task
requires stay byte-identical to main, and nothing else re-exposes it.
Reconstructing a count from estadoStream's reconectando emissions
would not be faithful (the stream can emit it many times per actual
backoff attempt), so that was deliberately not attempted.

test/pantallas/pantalla_paises_test.dart

@@ -66,9 +66,12 @@ void main() {
 
       // Full alphabetical list: all 3 fetched countries render.
       expect(find.text('Argentina'), findsOneWidget);
-      expect(find.text('France'), findsOneWidget);
-      // 'Spain' renders twice: "Tus idiomas" (locale es -> representative
-      // country ES) AND the full list below.
+      // 'France' and 'Spain' each render twice: once in "Tus idiomas" (FR
+      // and ES both back a supported locale) and once in the full list
+      // below. Item 24's row now shows the name as its OWN Text (not
+      // concatenated with the count into one Chip label), so both are
+      // independently findable in each section.
+      expect(find.text('France'), findsWidgets);
       expect(find.text('Spain'), findsWidgets);
 
       // Each entry's parsed `stationcount` renders via the existing
@@ -77,10 +80,127 @@ void main() {
       // as a plain number here, never throwing a cast error.
       expect(find.text(l10n.stationsCount(482)), findsWidgets);
       expect(find.text(l10n.stationsCount(120)), findsOneWidget);
-      expect(find.text(l10n.stationsCount(75)), findsOneWidget);
+      // Also doubled, for the same reason as 'France' above.
+      expect(find.text(l10n.stationsCount(75)), findsWidgets);
     },
   );
 
+  // Item 24 / audit 5.1-5.3, 5.5 (t4:256-269): tappable ISO rows, not
+  // non-interactive chips/plain ListTiles.
+  group('Item 24 -- tappable ISO rows', () {
+    testWidgets('rows show the ISO code and no longer use Chip or ListTile', (
+      tester,
+    ) async {
+      final estado = EstadoBusqueda(
+        radio: FakeServicioRadio(
+          paises: const [
+            PaisRadio(nombre: 'Spain', codigoIso: 'ES', numeroEmisoras: 482),
+            PaisRadio(
+              nombre: 'Argentina',
+              codigoIso: 'AR',
+              numeroEmisoras: 120,
+            ),
+          ],
+        ),
+      );
+      addTearDown(estado.dispose);
+
+      await tester.pumpWidget(buildScreen(estado));
+      await pumpEstable(tester);
+
+      expect(
+        find.byType(Chip),
+        findsNothing,
+        reason: 'audit 5.1 replaces the Wrap-of-Chip with tappable rows',
+      );
+      expect(
+        find.byType(ListTile),
+        findsNothing,
+        reason:
+            'audit 5.3 rows need an ISO-code column a plain ListTile '
+            'has no slot for',
+      );
+      expect(find.text('AR'), findsOneWidget);
+      // 'ES' renders in BOTH the "Tus idiomas" and "Todos" rows.
+      expect(find.text('ES'), findsWidgets);
+      expect(find.byIcon(Icons.chevron_right_rounded), findsWidgets);
+    });
+
+    testWidgets('tapping a row invokes onPaisSeleccionado with that country', (
+      tester,
+    ) async {
+      final estado = EstadoBusqueda(
+        radio: FakeServicioRadio(
+          paises: const [
+            PaisRadio(
+              nombre: 'Argentina',
+              codigoIso: 'AR',
+              numeroEmisoras: 120,
+            ),
+          ],
+        ),
+      );
+      addTearDown(estado.dispose);
+      PaisRadio? seleccionado;
+
+      await tester.pumpWidget(
+        ChangeNotifierProvider<EstadoBusqueda>.value(
+          value: estado,
+          child: MaterialApp(
+            locale: const Locale('es'),
+            localizationsDelegates: AppLocalizations.localizationsDelegates,
+            supportedLocales: AppLocalizations.supportedLocales,
+            home: PantallaPaises(
+              onPaisSeleccionado: (pais) => seleccionado = pais,
+            ),
+          ),
+        ),
+      );
+      await pumpEstable(tester);
+
+      await tester.tap(find.text('Argentina'));
+      await pumpEstable(tester);
+
+      expect(seleccionado?.codigoIso, 'AR');
+    });
+
+    testWidgets(
+      'the first "Tus idiomas" row is highlighted: teal-tinted background, '
+      'bold name',
+      (tester) async {
+        final estado = EstadoBusqueda(
+          radio: FakeServicioRadio(
+            paises: const [
+              PaisRadio(nombre: 'Spain', codigoIso: 'ES', numeroEmisoras: 482),
+            ],
+          ),
+        );
+        addTearDown(estado.dispose);
+
+        await tester.pumpWidget(buildScreen(estado));
+        await pumpEstable(tester);
+
+        final nombre = tester.widget<Text>(find.text('Spain').first);
+        expect(nombre.style?.fontWeight, FontWeight.w800);
+
+        final decorado = tester.widget<DecoratedBox>(
+          find
+              .ancestor(
+                of: find.text('Spain').first,
+                matching: find.byType(DecoratedBox),
+              )
+              .first,
+        );
+        final decoration = decorado.decoration as BoxDecoration;
+        expect(
+          decoration.color,
+          isNot(Colors.transparent),
+          reason: 't4:256 the first row is teal-tinted, not transparent',
+        );
+      },
+    );
+  });
+
   testWidgets(
     'cargarPaises no se re-dispara si ya hay datos en caché al reconstruir',
     (tester) async {