fix: resolver advertencias de analisis i18n

lib/pantallas/pantalla_ajustes.dart

@@ -1161,6 +1161,7 @@ class _SeccionBackup extends StatelessWidget {
   const _SeccionBackup();
 
   Future<void> _exportar(BuildContext context) async {
+    final l10n = AppLocalizations.of(context);
     try {
       final estado = context.read<EstadoRadio>();
       final config = await estado.exportarConfig();
@@ -1172,17 +1173,15 @@ class _SeccionBackup extends StatelessWidget {
 
       await Share.shareXFiles(
         [XFile(file.path)],
-        subject: AppLocalizations.of(context).backupShareSubject,
-        text: AppLocalizations.of(
-          context,
-        ).backupShareText(DateTime.now().toLocal()),
+        subject: l10n.backupShareSubject,
+        text: l10n.backupShareText(DateTime.now().toLocal()),
       );
     } catch (e) {
       if (context.mounted) {
         ScaffoldMessenger.of(context).showSnackBar(
           SnackBar(
             content: Text(
-              AppLocalizations.of(context).backupExportError(e.toString()),
+              l10n.backupExportError(e.toString()),
             ),
           ),
         );
@@ -1191,6 +1190,7 @@ class _SeccionBackup extends StatelessWidget {
   }
 
   Future<void> _importar(BuildContext context) async {
+    final l10n = AppLocalizations.of(context);
     try {
       final result = await FilePicker.platform.pickFiles(
         type: FileType.custom,
@@ -1230,7 +1230,7 @@ class _SeccionBackup extends StatelessWidget {
           await estado.importarConfig(json);
           messenger.showSnackBar(
             SnackBar(
-              content: Text(AppLocalizations.of(context).backupImportSuccess),
+              content: Text(l10n.backupImportSuccess),
             ),
           );
         }
@@ -1240,7 +1240,7 @@ class _SeccionBackup extends StatelessWidget {
         ScaffoldMessenger.of(context).showSnackBar(
           SnackBar(
             content: Text(
-              AppLocalizations.of(context).backupImportError(e.toString()),
+              l10n.backupImportError(e.toString()),
             ),
           ),
         );

lib/pantallas/pantalla_alarmas.dart

@@ -367,7 +367,7 @@ class _EditorAlarmaSheetState extends State<_EditorAlarmaSheet> {
     _tipo = alarma?.tipoProgramacion ?? TipoProgramacionAlarma.unica;
     _diasSemana = {...alarma?.diasSemana ?? const <int>[]};
     _volumen = alarma?.volumen ?? 0.85;
-    _fadeInSegundos = ((alarma?.fadeInSegundos ?? 0).clamp(0, 60)) as int;
+    _fadeInSegundos = (alarma?.fadeInSegundos ?? 0).clamp(0, 60).toInt();
     _sonarEnVacaciones = alarma?.sonarEnVacaciones ?? true;
     _sonidoInterno = alarma?.sonidoInterno ?? SonidoInternoAlarma.amanecer;
     _emisora = alarma?.emisora ?? context.read<EstadoRadio>().emisoraPreferida;
@@ -681,7 +681,7 @@ class _EditorAlarmaSheetState extends State<_EditorAlarmaSheet> {
           sonarEnVacaciones: _sonarEnVacaciones,
           snoozeMinutos: existente?.snoozeMinutos ?? 5,
           volumen: _volumen,
-          fadeInSegundos: _fadeInSegundos.clamp(0, 60),
+          fadeInSegundos: _fadeInSegundos.clamp(0, 60).toInt(),
           sonidoInterno: _sonidoInterno,
           activa: true,
         );

lib/pantallas/pantalla_buscar.dart

@@ -3,7 +3,6 @@ import 'package:flutter_animate/flutter_animate.dart';
 import 'package:provider/provider.dart';
 
 import '../estado/estado_radio.dart';
-import '../l10n/app_localizations_ext.dart';
 import '../l10n/gen/app_localizations.dart';
 import '../widgets/pluri_glass_surface.dart';
 import '../widgets/pluri_icon.dart';

lib/pantallas/pantalla_reproductor.dart

@@ -553,7 +553,7 @@ class _GrabacionWidget extends StatelessWidget {
             actions: [
               TextButton(
                 onPressed: () => Navigator.pop(ctx),
-                child: Text(AppLocalizations.of(ctx).cancelAction),
+                child: Text(AppLocalizations.of(context).cancelAction),
               ),
               FilledButton(
                 onPressed: () {
@@ -803,7 +803,7 @@ class _TimerWidget extends StatelessWidget {
                 visualDensity: VisualDensity.compact,
                 padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
               ),
-              child: Text(AppLocalizations.of(ctx).cancelAction),
+              child: Text(AppLocalizations.of(context).cancelAction),
             ),
           ],
         );