Add translations for Google Play Games error messages

- Add error message translations for signing in, showing leaderboards, and showing achievements
- Support for English, Hungarian, and German languages
- Replace hardcoded error strings with localized versions

🤖 Generated with [Claude Code](https://claude.ai/code)

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

lib/l10n/app_de.arb

@@ -144,5 +144,8 @@
   "signIn": "Anmelden",
   "signInSuccess": "Erfolgreich bei Google Play Spiele angemeldet!",
   "signInFailed": "Anmeldung bei Google Play Spiele fehlgeschlagen",
-  "signOutSuccess": "Von Google Play Spiele abgemeldet"
+  "signOutSuccess": "Von Google Play Spiele abgemeldet",
+  "errorSigningIn": "Fehler bei der Anmeldung: {error}",
+  "errorShowingLeaderboards": "Fehler beim Anzeigen der Bestenlisten: {error}",
+  "errorShowingAchievements": "Fehler beim Anzeigen der Erfolge: {error}"
 }

lib/l10n/app_en.arb

@@ -612,5 +612,32 @@
   "signOutSuccess": "Signed out from Google Play Games",
   "@signOutSuccess": {
     "description": "Sign out success message"
+  },
+  "errorSigningIn": "Error signing in: {error}",
+  "@errorSigningIn": {
+    "description": "Error message when signing in fails",
+    "placeholders": {
+      "error": {
+        "type": "String"
+      }
+    }
+  },
+  "errorShowingLeaderboards": "Error showing leaderboards: {error}",
+  "@errorShowingLeaderboards": {
+    "description": "Error message when showing leaderboards fails",
+    "placeholders": {
+      "error": {
+        "type": "String"
+      }
+    }
+  },
+  "errorShowingAchievements": "Error showing achievements: {error}",
+  "@errorShowingAchievements": {
+    "description": "Error message when showing achievements fails",
+    "placeholders": {
+      "error": {
+        "type": "String"
+      }
+    }
   }
 }

lib/l10n/app_hu.arb

@@ -144,5 +144,8 @@
   "signIn": "Bejelentkezés",
   "signInSuccess": "Sikeresen bejelentkezett a Google Play Játékokba!",
   "signInFailed": "Google Play Játékokba való bejelentkezés sikertelen",
-  "signOutSuccess": "Kijelentkezett a Google Play Játékokból"
+  "signOutSuccess": "Kijelentkezett a Google Play Játékokból",
+  "errorSigningIn": "Hiba a bejelentkezésnél: {error}",
+  "errorShowingLeaderboards": "Hiba a ranglista megjelenítésénél: {error}",
+  "errorShowingAchievements": "Hiba az eredmények megjelenítésénél: {error}"
 }

lib/l10n/app_localizations.dart

@@ -963,6 +963,24 @@ abstract class AppLocalizations {
   /// In en, this message translates to:
   /// **'Signed out from Google Play Games'**
   String get signOutSuccess;
+
+  /// Error message when signing in fails
+  ///
+  /// In en, this message translates to:
+  /// **'Error signing in: {error}'**
+  String errorSigningIn(String error);
+
+  /// Error message when showing leaderboards fails
+  ///
+  /// In en, this message translates to:
+  /// **'Error showing leaderboards: {error}'**
+  String errorShowingLeaderboards(String error);
+
+  /// Error message when showing achievements fails
+  ///
+  /// In en, this message translates to:
+  /// **'Error showing achievements: {error}'**
+  String errorShowingAchievements(String error);
 }
 
 class _AppLocalizationsDelegate

lib/l10n/app_localizations_de.dart

@@ -466,4 +466,19 @@ class AppLocalizationsDe extends AppLocalizations {
 
   @override
   String get signOutSuccess => 'Von Google Play Spiele abgemeldet';
+
+  @override
+  String errorSigningIn(String error) {
+    return 'Fehler bei der Anmeldung: $error';
+  }
+
+  @override
+  String errorShowingLeaderboards(String error) {
+    return 'Fehler beim Anzeigen der Bestenlisten: $error';
+  }
+
+  @override
+  String errorShowingAchievements(String error) {
+    return 'Fehler beim Anzeigen der Erfolge: $error';
+  }
 }

lib/l10n/app_localizations_en.dart

@@ -460,4 +460,19 @@ class AppLocalizationsEn extends AppLocalizations {
 
   @override
   String get signOutSuccess => 'Signed out from Google Play Games';
+
+  @override
+  String errorSigningIn(String error) {
+    return 'Error signing in: $error';
+  }
+
+  @override
+  String errorShowingLeaderboards(String error) {
+    return 'Error showing leaderboards: $error';
+  }
+
+  @override
+  String errorShowingAchievements(String error) {
+    return 'Error showing achievements: $error';
+  }
 }

lib/l10n/app_localizations_hu.dart

@@ -464,4 +464,19 @@ class AppLocalizationsHu extends AppLocalizations {
 
   @override
   String get signOutSuccess => 'Kijelentkezett a Google Play Játékokból';
+
+  @override
+  String errorSigningIn(String error) {
+    return 'Hiba a bejelentkezésnél: $error';
+  }
+
+  @override
+  String errorShowingLeaderboards(String error) {
+    return 'Hiba a ranglista megjelenítésénél: $error';
+  }
+
+  @override
+  String errorShowingAchievements(String error) {
+    return 'Hiba az eredmények megjelenítésénél: $error';
+  }
 }

lib/ui/google_play_games_widget.dart

@@ -198,7 +198,7 @@ class _GooglePlayGamesWidgetState extends State<GooglePlayGamesWidget> {
       if (!mounted) return;
       ScaffoldMessenger.of(context).showSnackBar(
         SnackBar(
-          content: Text('Error signing in: $e'),
+          content: Text(l10n.errorSigningIn(e.toString())),
           backgroundColor: Colors.red,
         ),
       );
@@ -231,7 +231,7 @@ class _GooglePlayGamesWidgetState extends State<GooglePlayGamesWidget> {
       if (!mounted) return;
       ScaffoldMessenger.of(context).showSnackBar(
         SnackBar(
-          content: Text('Error showing leaderboards: $e'),
+          content: Text(l10n.errorShowingLeaderboards(e.toString())),
           backgroundColor: Colors.red,
         ),
       );
@@ -245,7 +245,7 @@ class _GooglePlayGamesWidgetState extends State<GooglePlayGamesWidget> {
       if (!mounted) return;
       ScaffoldMessenger.of(context).showSnackBar(
         SnackBar(
-          content: Text('Error showing achievements: $e'),
+          content: Text(l10n.errorShowingAchievements(e.toString())),
           backgroundColor: Colors.red,
         ),
       );