feat(app): scaffolding initial du projet Flutter GameTime

Structure Flutter iOS/Android (lib/ organisé en couches domain,
application, infrastructure, presentation), intégration Drift pour la
persistance locale (sqlite3_flutter_libs), configuration des plateformes
android/ et ios/. Build APK debug validé.

Ajuste le .gitignore pour ignorer l'état d'exécution IdeA
(.ideai/permissions.json) au même titre que le reste du runtime.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

test/domain_import_boundaries_test.dart

@@ -0,0 +1,25 @@
+import 'dart:io';
+
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  test('domain layer does not import Flutter or Drift', () {
+    final domainDirectory = Directory('lib/domain');
+    final dartFiles = domainDirectory
+        .listSync(recursive: true)
+        .whereType<File>()
+        .where((file) => file.path.endsWith('.dart'));
+
+    for (final file in dartFiles) {
+      final source = file.readAsStringSync();
+
+      expect(source, isNot(contains('package:flutter/')), reason: file.path);
+      expect(source, isNot(contains('package:drift/')), reason: file.path);
+      expect(
+        source,
+        isNot(contains('package:drift_flutter/')),
+        reason: file.path,
+      );
+    }
+  });
+}