feat(dependencies): add rxdart package and improve string extension methods for better handling of empty strings and gender parsing

test/features/complaining/models/complain_model_test.dart

@@ -0,0 +1,36 @@
+import 'package:eatvio_app/features/complaining/models/complain_model.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+void main() {
+  group('ComplainModel', () {
+    test('создает ComplainModel с дефолтными значениями', () {
+      const model = ComplainModel();
+
+      expect(model.description, isNull);
+      expect(model.tags, isEmpty);
+    });
+
+    test('создает ComplainModel с описанием и тегами', () {
+      const model = ComplainModel(
+        description: 'Test complaint',
+        tags: ['tag1', 'tag2'],
+      );
+
+      expect(model.description, 'Test complaint');
+      expect(model.tags, ['tag1', 'tag2']);
+    });
+
+    test('fromJson создает ComplainModel из JSON', () {
+      final json = {
+        'description': 'Test complaint',
+        'tags': ['tag1', 'tag2'],
+      };
+
+      final model = ComplainModel.fromJson(json);
+
+      expect(model.description, 'Test complaint');
+      expect(model.tags, ['tag1', 'tag2']);
+    });
+  });
+}
+