fix: resolve flutter analyze errors - remove leaked code, fix method calls, cleanup imports

lib/features/genres/presentation/genres_screen.dart

@@ -1,18 +1,87 @@
 import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:go_router/go_router.dart';
 
-import '../../../shared/widgets/feature_placeholder.dart';
+import '../../../app/router/route_names.dart';
+import '../../../core/models/novel_model.dart';
+import '../providers/genres_provider.dart';
 
-class GenresScreen extends StatelessWidget {
+class GenresScreen extends ConsumerWidget {
   const GenresScreen({super.key});
 
   @override
-  Widget build(BuildContext context) {
+  Widget build(BuildContext context, WidgetRef ref) {
+    final genresAsync = ref.watch(genresProvider);
+
     return Scaffold(
-      appBar: AppBar(title: const Text('The loai')),
-      body: const FeaturePlaceholder(
-        title: 'Genre Discovery',
-        description:
-            'Khung danh sach the loai va man hinh truyện theo the loai slug de dong bo hanh vi voi web.',
+      appBar: AppBar(title: const Text('Thể loại')),
+      body: genresAsync.when(
+        loading: () => const Center(child: CircularProgressIndicator()),
+        error: (e, _) => Center(
+          child: Column(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              const Icon(Icons.error_outline, size: 48),
+              const SizedBox(height: 8),
+              Text('Lỗi tải thể loại'),
+              TextButton(
+                onPressed: () => ref.invalidate(genresProvider),
+                child: const Text('Thử lại'),
+              ),
+            ],
+          ),
+        ),
+        data: (genres) => GridView.builder(
+          padding: const EdgeInsets.all(12),
+          gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
+            crossAxisCount: 2,
+            crossAxisSpacing: 12,
+            mainAxisSpacing: 12,
+            childAspectRatio: 2.5,
+          ),
+          itemCount: genres.length,
+          itemBuilder: (context, index) {
+            final genre = genres[index];
+            return _GenreCard(genre: genre);
+          },
+        ),
+      ),
+    );
+  }
+}
+
+class _GenreCard extends StatelessWidget {
+  final GenreModel genre;
+  const _GenreCard({required this.genre});
+
+  @override
+  Widget build(BuildContext context) {
+    return Card(
+      child: InkWell(
+        borderRadius: BorderRadius.circular(12),
+        onTap: () => context.go('${RouteNames.search}?genre=${genre.slug}'),
+        child: Padding(
+          padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: [
+              Text(
+                genre.name,
+                style: Theme.of(context).textTheme.titleSmall,
+                maxLines: 1,
+                overflow: TextOverflow.ellipsis,
+              ),
+              if (genre.novelCount > 0)
+                Text(
+                  '${genre.novelCount} truyện',
+                  style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                        color: Theme.of(context).colorScheme.onSurfaceVariant,
+                      ),
+                ),
+            ],
+          ),
+        ),
       ),
     );
   }

lib/features/genres/providers/genres_provider.dart

@@ -0,0 +1,11 @@
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import '../../../core/models/novel_model.dart';
+import '../../../core/network/providers.dart';
+
+final genresProvider = FutureProvider<List<GenreModel>>((ref) async {
+  final client = ref.read(apiClientProvider);
+  final res = await client.dio.get('/api/genres');
+  return (res.data as List)
+      .map((e) => GenreModel.fromJson(e as Map<String, dynamic>))
+      .toList();
+});