fix(bienvenida,grabaciones): headline size, CTA radius, storage caption

Screen 14 / audit 14.3+14.7: welcome headline now 34px/ls-1.2 (was
headlineMedium's 28/ls-1.0), CTA restyled to a radius-18 rounded
rectangle instead of Material 3's default StadiumBorder (t4:696,715).

Screen 12 / audit 12.2+12.3: the recordings storage card now shows the
bold "X of Y used" headline ABOVE a 6px/radius-3 bar, followed by a
real folder-path + purge-policy caption below it -- was the bar first
with the "used" string as its only (small, generic) caption (t4:613).
New ARB key recordingsLibraryStorageFolderCaption, translated to all
13 locales.

Item 12.5 (folder/max-size settings living behind the header action
instead of inline on this screen) is a deliberate structural split
from WU15b; the audit itself scopes it out of this pass.

lib/l10n/gen/app_localizations_it.dart

@@ -448,6 +448,10 @@ class AppLocalizationsIt extends AppLocalizations {
     return '$usedMb MB di $totalMb MB usati';
   }
 
+  @override
+  String get recordingsLibraryStorageFolderCaption =>
+      'Music/PluriWave · elimina le più vecchie al raggiungimento del limite';
+
   @override
   String get recordingsLibraryEmptyTitle => 'Ancora nessuna registrazione';
 
@@ -622,12 +626,20 @@ class AppLocalizationsIt extends AppLocalizations {
   @override
   String get searchMinQualityFilterLabel => 'Qualità minima';
 
+  @override
+  String get searchLoadingStationsLabel => 'RICERCA STAZIONI IN CORSO…';
+
   @override
   String get searchEmptyTitle => 'Cerca un\'emittente';
 
   @override
   String get searchNoResultsTitle => 'Nessun risultato';
 
+  @override
+  String searchNoResultsForQueryTitle(Object query) {
+    return 'Nessun risultato per \"$query\"';
+  }
+
   @override
   String get searchEmptySubtitle =>
       'Usa la barra in alto o i chip per scoprire emittenti da tutto il mondo.';
@@ -661,6 +673,9 @@ class AppLocalizationsIt extends AppLocalizations {
   @override
   String get countriesScreenTitle => 'Paesi';
 
+  @override
+  String get countriesSearchHint => 'Paese o codice...';
+
   @override
   String get countriesYourLanguagesTitle => 'Le tue lingue';
 
@@ -1023,6 +1038,9 @@ class AppLocalizationsIt extends AppLocalizations {
     return '$minutes min';
   }
 
+  @override
+  String get alarmSnoozeUsualLabel => 'abituale';
+
   @override
   String get saveFavoritesAlarmHint =>
       'Salva emittenti nei Preferiti per usarle come sveglia musicale.';
@@ -1371,6 +1389,9 @@ class AppLocalizationsIt extends AppLocalizations {
     return 'Giorni: $days';
   }
 
+  @override
+  String get alarmRepeatSectionLabel => 'RIPETI';
+
   @override
   String get androidReliabilityTitle => 'Controlla affidabilità Android';