fix(favoritos): stop the header padding from doubling up

Issue 3 (feedback-pruebas): ReorderableListView.padding wrapped
header/rows/footer with a single horizontal value (16), which doubled
up on top of PluriRootHeader's own internal inset -- landing the
title at 36px instead of the 20px every other root uses -- while also
applying card-tier padding to the flat FilaEmisoraPlana rows (row
tier, matching the same widget's fix on Buscar) and leaving the
populated-state top gap at an unwired 4 that didn't match this same
screen's own empty state (0) or the footer CTA's prototype value (8).

Zeroes the list-level padding and gives the header, chip strip, rows,
and footer CTA their own correctly-tiered insets instead.

lib/pantallas/pantalla_favoritos.dart

@@ -174,12 +174,18 @@ class _PantallaFavoritosState extends State<PantallaFavoritos> {
 
     return ReorderableListView(
       buildDefaultDragHandles: false,
-      padding: const EdgeInsets.fromLTRB(
+      // Issue 3 (feedback-pruebas): zero horizontal here, matching every
-        PluriLayout.horizontal,
+      // other root's PluriLayout.pageListPadding convention (Alarmas,
-        4,
+      // Ajustes, and this screen's OWN empty-state branch above).
-        PluriLayout.horizontal,
+      // ReorderableListView.padding wraps header/children/footer UNIFORMLY,
-        PluriLayout.bottomChromeInset,
+      // so a single horizontal value here can never be simultaneously right
-      ),
+      // for PluriRootHeader (self-padded, wants none), the reorderable rows
+      // (want row tier, applied per item below) and the footer CTA (wants
+      // card tier, applied on the footer's own Padding below). The previous
+      // `PluriLayout.horizontal` doubled up on top of PluriRootHeader's own
+      // internal inset, pushing "Favorites" in by 36px instead of the 20px
+      // every other root uses for its title.
+      padding: const EdgeInsets.only(bottom: PluriLayout.bottomChromeInset),
       header: Padding(
         padding: const EdgeInsets.only(bottom: 12),
         child: Column(
@@ -224,17 +230,39 @@ class _PantallaFavoritosState extends State<PantallaFavoritos> {
               ],
             ),
             const SizedBox(height: 12),
-            _FilaChipsGrupos(
+            // Issue 3 (feedback-pruebas): t4:218 draws this chip strip at
+            // title-tier (20px) horizontal inset, directly on the page
+            // background -- it now needs its OWN inset since the list's
+            // padding no longer supplies one.
+            Padding(
+              padding: const EdgeInsets.symmetric(
+                horizontal: PluriLayout.titleHorizontal,
+              ),
+              child: _FilaChipsGrupos(
                 grupos: gruposVisibles,
                 favoritos: favoritos,
                 seleccionado: seleccionEfectiva,
-              onSeleccionar: (id) => setState(() => _grupoSeleccionadoId = id),
+                onSeleccionar:
+                    (id) => setState(() => _grupoSeleccionadoId = id),
+              ),
             ),
           ],
         ),
       ),
       footer: Padding(
-        padding: const EdgeInsets.only(top: 4),
+        // Issue 3 (feedback-pruebas): card tier (16, matching every other
+        // screen's dashed CTA) now that the list's own padding no longer
+        // supplies it, plus t4:234's 8px gap above the CTA
+        // (PluriLayout.compactGap) instead of the previous unwired literal
+        // 4 -- the ONLY state of this screen with a nonzero top gap before
+        // its own content used a value that matched neither this screen's
+        // own empty-state branch nor the prototype.
+        padding: const EdgeInsets.fromLTRB(
+          PluriLayout.horizontal,
+          PluriLayout.compactGap,
+          PluriLayout.horizontal,
+          0,
+        ),
         child: _CtaEmisoraPersonalizada(
           onTap: _abrirFormularioEmisoraPersonalizada,
         ),
@@ -244,8 +272,17 @@ class _PantallaFavoritosState extends State<PantallaFavoritos> {
               _onReorder(filtrados, favoritos, oldIndex, newIndex),
       children: [
         for (var i = 0; i < filtrados.length; i++)
-          _FilaFavorito(
+          // Issue 3 (feedback-pruebas): row tier (12), not card tier -- the
+          // key moves to this wrapper (ReorderableListView identifies each
+          // child by its own top-level key) since FilaEmisoraPlana rows are
+          // documented (audit 4.3) as flat, background-less rows, the same
+          // tier Buscar's results list already uses for the same widget.
+          Padding(
             key: ValueKey(filtrados[i].uuid),
+            padding: const EdgeInsets.symmetric(
+              horizontal: PluriLayout.rowHorizontal,
+            ),
+            child: _FilaFavorito(
               index: i,
               emisora: filtrados[i],
               grupos: gruposVisibles,
@@ -254,6 +291,7 @@ class _PantallaFavoritosState extends State<PantallaFavoritos> {
                 orElse: () => gruposVisibles.first,
               ),
             ),
+          ),
       ],
     );
   }
@@ -343,7 +381,6 @@ class _FilaChipsGrupos extends StatelessWidget {
 
 class _FilaFavorito extends StatelessWidget {
   const _FilaFavorito({
-    super.key,
     required this.index,
     required this.emisora,
     required this.grupos,

test/pantallas/pantalla_favoritos_test.dart

@@ -7,7 +7,9 @@ import 'package:pluriwave/l10n/gen/app_localizations.dart';
 import 'package:pluriwave/pantallas/ajustes/pantalla_ajustes_grupos_favoritos.dart';
 import 'package:pluriwave/pantallas/pantalla_favoritos.dart';
 import 'package:pluriwave/widgets/fila_emisora_plana.dart';
+import 'package:pluriwave/widgets/pluri_layout.dart';
 import 'package:pluriwave/widgets/pluri_push_scaffold.dart';
+import 'package:pluriwave/widgets/pluri_root_header.dart';
 import 'package:pluriwave/widgets/tarjeta_emisora.dart';
 import 'package:provider/provider.dart';
 import 'package:shared_preferences/shared_preferences.dart';
@@ -546,6 +548,106 @@ void main() {
       expect(inactivo.backgroundColor, const Color(0xFF102532));
     });
   });
+
+  group('Issue 3 (feedback-pruebas): spacing tiers', () {
+    testWidgets('the header title sits at title-tier inset (20px) -- '
+        'ReorderableListView.padding used to double up on top of '
+        "PluriRootHeader's own internal inset", (tester) async {
+      setLargeSurface(tester);
+      _suppressListTileInkAssertion();
+      final estado = await crearEstadoConFavoritos();
+      addTearDown(estado.dispose);
+      final l10n = lookupAppLocalizations(const Locale('en'));
+
+      await tester.pumpWidget(buildScreen(estado));
+      await pumpStable(tester);
+
+      final titulo = find.descendant(
+        of: find.byType(PluriRootHeader),
+        matching: find.text(l10n.favoritesTitle),
+      );
+      expect(
+        tester.getTopLeft(titulo).dx,
+        PluriLayout.titleHorizontal,
+        reason:
+            'PluriRootHeader already supplies its own 20px inset; the '
+            'previous ReorderableListView.padding of 16 doubled up on top '
+            'of it, landing the title at 36px instead of 20px -- the ONE '
+            "root screen whose header didn't match Alarmas/Ajustes",
+      );
+    });
+
+    testWidgets(
+      'the header sits at the SAME horizontal position whether the list is '
+      'empty or populated -- two mutually-exclusive states of the same '
+      'header must not read differently',
+      (tester) async {
+        setLargeSurface(tester);
+        final l10n = lookupAppLocalizations(const Locale('en'));
+
+        final vacio = await crearEstadoVacio();
+        addTearDown(vacio.dispose);
+        await tester.pumpWidget(buildScreen(vacio));
+        await pumpStable(tester);
+        final dxVacio =
+            tester
+                .getTopLeft(
+                  find.descendant(
+                    of: find.byType(PluriRootHeader),
+                    matching: find.text(l10n.favoritesTitle),
+                  ),
+                )
+                .dx;
+
+        _suppressListTileInkAssertion();
+        final conFavoritos = await crearEstadoConFavoritos();
+        addTearDown(conFavoritos.dispose);
+        await tester.pumpWidget(buildScreen(conFavoritos));
+        await pumpStable(tester);
+        final dxConFavoritos =
+            tester
+                .getTopLeft(
+                  find.descendant(
+                    of: find.byType(PluriRootHeader),
+                    matching: find.text(l10n.favoritesTitle),
+                  ),
+                )
+                .dx;
+
+        expect(
+          dxConFavoritos,
+          dxVacio,
+          reason:
+              'the empty and populated branches of this screen must render '
+              'the SAME header inset -- they previously did not (0 vs 16 '
+              'extra px of list-level padding)',
+        );
+      },
+    );
+
+    testWidgets(
+      'each favourite row uses row-tier horizontal inset (12), not the '
+      'card-tier constant a background-less row was never meant to carry',
+      (tester) async {
+        setLargeSurface(tester);
+        _suppressListTileInkAssertion();
+        final estado = await crearEstadoConFavoritos();
+        addTearDown(estado.dispose);
+
+        await tester.pumpWidget(buildScreen(estado));
+        await pumpStable(tester);
+
+        expect(
+          tester.getTopLeft(find.byType(FilaEmisoraPlana).first).dx,
+          PluriLayout.rowHorizontal,
+          reason:
+              'audit 4.3: background-less rows are row tier (12), matching '
+              'the same widget already fixed on Buscar -- not card tier '
+              '(16)',
+        );
+      },
+    );
+  });
 }
 
 void setLargeSurface(WidgetTester tester) {