Notrufnummern-Datenbasis, Ländererkennung, State-Management und Lokalisierung (AP1-AP7)

Implementiert den kompletten Kern-Flow der Emergency App gemäß docs/plan.md:
- Notrufnummern-Datenbasis für 199 Länder + Modelle/Repository (AP1)
- DialerService für tel:-Notrufe ohne Auto-Dial (AP2)
- Statisches UI mit Panik-Button-Fallback (AP3)
- Priorisierte Ländererkennung: SIM/Netz -> GPS/Geocoding -> Cache (AP4)
- EmergencyProvider verdrahtet Repository/LocationService mit der UI (AP5)
- Manuelle Länderauswahl als Fallback samt eigener Priorität (AP6)
- UI-Lokalisierung (de/en/fr/es), an erkanntes Land gekoppelt (AP7)

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

lib/l10n/app_localizations.dart

@@ -5,7 +5,10 @@ import 'package:flutter/widgets.dart';
 import 'package:flutter_localizations/flutter_localizations.dart';
 import 'package:intl/intl.dart' as intl;
 
+import 'app_localizations_de.dart';
 import 'app_localizations_en.dart';
+import 'app_localizations_es.dart';
+import 'app_localizations_fr.dart';
 
 // ignore_for_file: type=lint
 
@@ -92,7 +95,72 @@ abstract class AppLocalizations {
       ];
 
   /// A list of this localizations delegate's supported locales.
-  static const List<Locale> supportedLocales = <Locale>[Locale('en')];
+  static const List<Locale> supportedLocales = <Locale>[
+    Locale('de'),
+    Locale('en'),
+    Locale('es'),
+    Locale('fr'),
+  ];
+
+  /// AppBar title of the home screen
+  ///
+  /// In en, this message translates to:
+  /// **'Emergency'**
+  String get appTitle;
+
+  /// Label of the button/tooltip used to open the manual country picker
+  ///
+  /// In en, this message translates to:
+  /// **'Select country manually'**
+  String get selectCountryButton;
+
+  /// Label of the button that retries country/number detection after an error
+  ///
+  /// In en, this message translates to:
+  /// **'Try again'**
+  String get retryButton;
+
+  /// Fallback error message shown when the provider does not report a specific error
+  ///
+  /// In en, this message translates to:
+  /// **'Unknown error while loading the emergency numbers.'**
+  String get errorGeneric;
+
+  /// Shown when the country could not be detected automatically (and no location permission info is shown separately)
+  ///
+  /// In en, this message translates to:
+  /// **'Country could not be determined.'**
+  String get countryUnknownMessage;
+
+  /// Shown when the detected country has no entry in the emergency number database
+  ///
+  /// In en, this message translates to:
+  /// **'Country not listed in the emergency number database. Only the global emergency number is available.'**
+  String get countryNotInDatabaseMessage;
+
+  /// AppBar title of the manual country picker screen
+  ///
+  /// In en, this message translates to:
+  /// **'Select country'**
+  String get pickerTitle;
+
+  /// Hint text of the search field in the manual country picker screen
+  ///
+  /// In en, this message translates to:
+  /// **'Search country'**
+  String get pickerSearchHint;
+
+  /// Empty state shown when the search filter matches no country
+  ///
+  /// In en, this message translates to:
+  /// **'No country found.'**
+  String get pickerNoResults;
+
+  /// Semantics/tooltip label of an emergency button, combining the number's label and the number itself
+  ///
+  /// In en, this message translates to:
+  /// **'{label}, call {number}'**
+  String emergencyButtonSemanticLabel(String label, String number);
 }
 
 class _AppLocalizationsDelegate
@@ -106,7 +174,7 @@ class _AppLocalizationsDelegate
 
   @override
   bool isSupported(Locale locale) =>
-      <String>['en'].contains(locale.languageCode);
+      <String>['de', 'en', 'es', 'fr'].contains(locale.languageCode);
 
   @override
   bool shouldReload(_AppLocalizationsDelegate old) => false;
@@ -115,8 +183,14 @@ class _AppLocalizationsDelegate
 AppLocalizations lookupAppLocalizations(Locale locale) {
   // Lookup logic when only language code is specified.
   switch (locale.languageCode) {
+    case 'de':
+      return AppLocalizationsDe();
     case 'en':
       return AppLocalizationsEn();
+    case 'es':
+      return AppLocalizationsEs();
+    case 'fr':
+      return AppLocalizationsFr();
   }
 
   throw FlutterError(