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.

lib/pantallas/pantalla_paises.dart

@@ -4,6 +4,7 @@ import 'package:provider/provider.dart';
 import '../estado/estado_busqueda.dart';
 import '../l10n/gen/app_localizations.dart';
 import '../modelos/pais_radio.dart';
+import '../tema/pluriwave_tokens.dart';
 import '../widgets/pluri_glass_surface.dart';
 import '../widgets/pluri_layout.dart';
 import '../widgets/pluri_push_scaffold.dart';
@@ -15,7 +16,14 @@ import '../widgets/pluri_push_scaffold.dart';
 /// live station counts already parsed from the API's `stationcount`
 /// **string** field (`PaisRadio.fromApi`, Engram id 2500).
 class PantallaPaises extends StatefulWidget {
-  const PantallaPaises({super.key});
+  const PantallaPaises({super.key, this.onPaisSeleccionado});
+
+  /// Item 24 / audit 5.2 (t4:256-269): every row is tappable (the prototype
+  /// draws a `chevron_right` on all of them). Optional so this screen stays
+  /// usable stand-alone; the one production call site
+  /// (`pantalla_buscar.dart`'s "Explorar por" grid) wires this to filter
+  /// search results by the tapped country and pop back.
+  final ValueChanged<PaisRadio>? onPaisSeleccionado;
 
   @override
   State<PantallaPaises> createState() => _PantallaPaisesState();
@@ -78,6 +86,10 @@ class _PantallaPaisesState extends State<PantallaPaises> {
     );
   }
 
+  void _seleccionar(PaisRadio pais) {
+    widget.onPaisSeleccionado?.call(pais);
+  }
+
   Widget _seccionTusIdiomas(
     BuildContext context,
     List<PaisRadio> paises,
@@ -105,18 +117,16 @@ class _PantallaPaisesState extends State<PantallaPaises> {
             ),
           ),
           const SizedBox(height: 8),
-          Wrap(
-            spacing: 8,
-            runSpacing: 8,
-            children: [
-              for (final pais in destacados)
-                Chip(
-                  label: Text(
-                    '${pais.nombre} · ${l10n.stationsCount(pais.numeroEmisoras)}',
-                  ),
-                ),
-            ],
-          ),
+          // Item 24 / audit 5.1 (t4:255-258): a column of tappable ISO
+          // rows, not a Wrap of non-interactive Chips.
+          for (final pais in destacados)
+            _FilaPais(
+              pais: pais,
+              l10n: l10n,
+              // Item 24 / audit 5.5 (t4:256): the first row is highlighted.
+              destacado: pais == destacados.first,
+              onTap: () => _seleccionar(pais),
+            ),
         ],
       ),
     );
@@ -140,22 +150,100 @@ class _PantallaPaisesState extends State<PantallaPaises> {
             ),
           ),
           const SizedBox(height: 4),
-          ListView.separated(
-            shrinkWrap: true,
-            physics: const NeverScrollableScrollPhysics(),
-            itemCount: paises.length,
-            separatorBuilder: (_, __) => const Divider(height: 1),
-            itemBuilder: (context, i) {
-              final pais = paises[i];
-              return ListTile(
-                contentPadding: EdgeInsets.zero,
-                title: Text(pais.nombre),
-                trailing: Text(l10n.stationsCount(pais.numeroEmisoras)),
-              );
-            },
-          ),
+          // Item 24 / audit 5.1-5.3 (t4:262-269): the same tappable ISO row
+          // as "Tus idiomas" -- not the previous ListTile, which had no ISO
+          // column and no onTap.
+          for (final pais in paises)
+            _FilaPais(pais: pais, l10n: l10n, onTap: () => _seleccionar(pais)),
         ],
       ),
     );
   }
 }
+
+/// Item 24 / audit 5.1-5.3, 5.5 (t4:256-269): a tappable row -- ISO code
+/// column, name, station count, and a chevron -- shared by "Tus idiomas"
+/// and "Todos". [destacado] applies the t4:256 highlight (teal-tinted
+/// background, bold name) reserved for the very first "Tus idiomas" row.
+class _FilaPais extends StatelessWidget {
+  const _FilaPais({
+    required this.pais,
+    required this.l10n,
+    this.destacado = false,
+    this.onTap,
+  });
+
+  final PaisRadio pais;
+  final AppLocalizations l10n;
+  final bool destacado;
+  final VoidCallback? onTap;
+
+  @override
+  Widget build(BuildContext context) {
+    final onSurface = Theme.of(context).colorScheme.onSurface;
+    return DecoratedBox(
+      decoration: BoxDecoration(
+        color:
+            destacado
+                ? PluriWaveTokens.brand.withValues(alpha: 0.1)
+                : Colors.transparent,
+        borderRadius: BorderRadius.circular(14),
+      ),
+      child: Material(
+        type: MaterialType.transparency,
+        child: InkWell(
+          borderRadius: BorderRadius.circular(14),
+          onTap: onTap,
+          child: Padding(
+            padding: const EdgeInsets.all(12),
+            child: Row(
+              children: [
+                // t4:256-258: 26px/lh1, centred in a 34-wide column.
+                SizedBox(
+                  width: 34,
+                  child: Text(
+                    pais.codigoIso,
+                    textAlign: TextAlign.center,
+                    style: const TextStyle(fontSize: 26, height: 1),
+                  ),
+                ),
+                const SizedBox(width: 14),
+                Expanded(
+                  child: Column(
+                    mainAxisSize: MainAxisSize.min,
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      Text(
+                        pais.nombre,
+                        style: TextStyle(
+                          fontSize: 15.5,
+                          fontWeight:
+                              destacado ? FontWeight.w800 : FontWeight.w700,
+                        ),
+                        maxLines: 1,
+                        overflow: TextOverflow.ellipsis,
+                      ),
+                      const SizedBox(height: 2),
+                      Text(
+                        l10n.stationsCount(pais.numeroEmisoras),
+                        style: TextStyle(
+                          fontSize: 12,
+                          color: onSurface.withValues(alpha: 0.55),
+                        ),
+                      ),
+                    ],
+                  ),
+                ),
+                Icon(
+                  Icons.chevron_right_rounded,
+                  size: 20,
+                  color: onSurface.withValues(alpha: 0.4),
+                ),
+              ],
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}