fix(ajustes): inset row dividers and shrink icon/title/chevron

Tier 4 visual fidelity, audit S10/10.6/10.8/10.9 (t4 lines 514-516):
GrupoAjustes' row divider now indents 47px instead of running
full-bleed, FilaAjuste's leading icon drops from Material's 24px
default to 21px, the row title is a local 14px override of cardTitle
(14.5), and the chevron shrinks to 19px at 40% opacity instead of the
24px full-opacity default.

test/pantallas/ajustes/widgets/fila_ajuste_test.dart

@@ -8,6 +8,24 @@ import 'package:pluriwave/tema/pluriwave_theme.dart';
 /// lines 512-539, 625 — "Voz clara", "Alta", "3 guardados", "Alfabético",
 /// "7 · 84 MB", "Español", "Hoy, 08:12", "200 MB"). `FilaAjuste` used to
 /// accept only `icon`/`titulo`/`onTap` — no value slot at all.
+/// Pre-existing project constraint (see `pantalla_ajustes_test.dart`):
+/// `PluriGlassSurface` paints a background over `ListTile`'s ink layer,
+/// which Flutter flags as a warning-level assertion, not a correctness bug.
+/// Only needed by the `GrupoAjustes` test below — the bare `FilaAjuste`
+/// tests above never wrap a `ListTile` inside that surface.
+void _suppressListTileInkAssertion() {
+  final original = FlutterError.onError;
+  FlutterError.onError = (details) {
+    if (details.exceptionAsString().contains(
+      'ListTile background color or ink splashes may be invisible',
+    )) {
+      return;
+    }
+    original?.call(details);
+  };
+  addTearDown(() => FlutterError.onError = original);
+}
+
 void main() {
   Widget host(Widget child) {
     return MaterialApp(
@@ -49,4 +67,59 @@ void main() {
     expect(find.text('Info'), findsOneWidget);
     expect(find.byIcon(Icons.chevron_right_rounded), findsOneWidget);
   });
+
+  testWidgets(
+    'visual fidelity (audit 10.6/10.8/10.9): leading icon is 21px, the '
+    'title is 14px, and the chevron is 19px at 40% opacity (t4 lines '
+    '514-515)',
+    (tester) async {
+      await tester.pumpWidget(
+        host(
+          FilaAjuste(
+            icon: Icons.equalizer_rounded,
+            titulo: 'Ecualizador base',
+            onTap: () {},
+          ),
+        ),
+      );
+
+      final icon = tester.widget<Icon>(find.byIcon(Icons.equalizer_rounded));
+      expect(icon.size, 21);
+
+      final titulo = tester.widget<Text>(find.text('Ecualizador base'));
+      expect(titulo.style?.fontSize, 14);
+
+      final chevron = tester.widget<Icon>(
+        find.byIcon(Icons.chevron_right_rounded),
+      );
+      expect(chevron.size, 19);
+      expect(chevron.color, const Color(0xFFF2F7FA).withValues(alpha: 0.4));
+    },
+  );
+
+  testWidgets(
+    'visual fidelity (audit S10): GrupoAjustes insets its row divider by '
+    '47px, not full-bleed (t4 line 516)',
+    (tester) async {
+      _suppressListTileInkAssertion();
+      await tester.pumpWidget(
+        host(
+          GrupoAjustes(
+            titulo: 'AUDIO',
+            filas: [
+              FilaAjuste(
+                icon: Icons.equalizer_rounded,
+                titulo: 'Uno',
+                onTap: () {},
+              ),
+              FilaAjuste(icon: Icons.hd_rounded, titulo: 'Dos', onTap: () {}),
+            ],
+          ),
+        ),
+      );
+
+      final divider = tester.widget<Divider>(find.byType(Divider));
+      expect(divider.indent, 47);
+    },
+  );
 }