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_de.dart

@@ -449,6 +449,10 @@ class AppLocalizationsDe extends AppLocalizations {
     return '$usedMb MB von $totalMb MB belegt';
   }
 
+  @override
+  String get recordingsLibraryStorageFolderCaption =>
+      'Music/PluriWave · älteste werden bei Erreichen des Limits gelöscht';
+
   @override
   String get recordingsLibraryEmptyTitle => 'Noch keine Aufnahmen';
 
@@ -622,12 +626,20 @@ class AppLocalizationsDe extends AppLocalizations {
   @override
   String get searchMinQualityFilterLabel => 'Mindestqualität';
 
+  @override
+  String get searchLoadingStationsLabel => 'SENDER WERDEN GESUCHT…';
+
   @override
   String get searchEmptyTitle => 'Suche nach einem Sender';
 
   @override
   String get searchNoResultsTitle => 'Keine Ergebnisse';
 
+  @override
+  String searchNoResultsForQueryTitle(Object query) {
+    return 'Keine Ergebnisse für „$query“';
+  }
+
   @override
   String get searchEmptySubtitle =>
       'Nutze die obere Leiste oder die Chips, um Sender aus aller Welt zu entdecken.';
@@ -661,6 +673,9 @@ class AppLocalizationsDe extends AppLocalizations {
   @override
   String get countriesScreenTitle => 'Länder';
 
+  @override
+  String get countriesSearchHint => 'Land oder Code...';
+
   @override
   String get countriesYourLanguagesTitle => 'Deine Sprachen';
 
@@ -1022,6 +1037,9 @@ class AppLocalizationsDe extends AppLocalizations {
     return '$minutes Min.';
   }
 
+  @override
+  String get alarmSnoozeUsualLabel => 'üblich';
+
   @override
   String get saveFavoritesAlarmHint =>
       'Speichere Sender in Favoriten, um sie als musikalischen Alarm zu verwenden.';
@@ -1368,6 +1386,9 @@ class AppLocalizationsDe extends AppLocalizations {
     return 'Tage: $days';
   }
 
+  @override
+  String get alarmRepeatSectionLabel => 'WIEDERHOLEN';
+
   @override
   String get androidReliabilityTitle => 'Android-Zuverlässigkeit prüfen';