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.

lib/pantallas/ajustes/widgets/fila_ajuste.dart

@@ -34,7 +34,9 @@ class GrupoAjustes extends StatelessWidget {
           Text(titulo, style: type.eyebrowLabel),
           const SizedBox(height: 4),
           for (var i = 0; i < filas.length; i++) ...[
-            if (i > 0) const Divider(height: 1),
+            // S10 (Tier 4 visual fidelity): the prototype insets its row
+            // divider by 47px (t4 line 516), not full-bleed.
+            if (i > 0) const Divider(height: 1, indent: 47),
             filas[i],
           ],
         ],
@@ -72,8 +74,14 @@ class FilaAjuste extends StatelessWidget {
     final valorActual = valor;
     return ListTile(
       contentPadding: EdgeInsets.zero,
-      leading: Icon(icon),
-      title: Text(titulo, style: type.cardTitle),
+      // 10.6 (Tier 4 visual fidelity): the prototype's row icon is 21px (t4
+      // line 514), not Material's 24px default.
+      leading: Icon(icon, size: 21),
+      // 10.8 (Tier 4 visual fidelity): the prototype's row title is
+      // 14px/w700 (t4 line 514); cardTitle is 14.5/w700 — a one-off
+      // override, not a new PluriWaveTypography style (mirrors the
+      // precedent set for the ringing screen's station name, audit 9.7).
+      title: Text(titulo, style: type.cardTitle.copyWith(fontSize: 14)),
       trailing: Row(
         mainAxisSize: MainAxisSize.min,
         children: [
@@ -88,7 +96,14 @@ class FilaAjuste extends StatelessWidget {
             ),
             const SizedBox(width: 6),
           ],
-          const Icon(Icons.chevron_right_rounded),
+          // 10.9 (Tier 4 visual fidelity): the prototype's chevron is 19px
+          // at 40% opacity (t4 lines 515-539), not Material's 24px
+          // full-opacity default.
+          Icon(
+            Icons.chevron_right_rounded,
+            size: 19,
+            color: const Color(0xFFF2F7FA).withValues(alpha: 0.4),
+          ),
         ],
       ),
       onTap: onTap,