다크 모드 전역 상태와 테마 기반 추가

userfront/lib/core/widgets/theme_toggle_button.dart

@@ -0,0 +1,44 @@
+import 'package:easy_localization/easy_localization.dart' hide tr;
+import 'package:flutter/material.dart';
+import 'package:userfront/i18n.dart';
+
+import '../theme/theme_controller.dart';
+
+class ThemeToggleButton extends StatelessWidget {
+  const ThemeToggleButton({super.key, this.compact = false});
+
+  final bool compact;
+
+  @override
+  Widget build(BuildContext context) {
+    context.locale;
+
+    return ValueListenableBuilder<ThemeMode>(
+      valueListenable: ThemeController.instance,
+      builder: (context, mode, _) {
+        final isLight = mode == ThemeMode.light;
+        final icon = isLight
+            ? Icons.light_mode_outlined
+            : Icons.dark_mode_outlined;
+        final label = isLight
+            ? tr('ui.common.theme_light', fallback: 'Light')
+            : tr('ui.common.theme_dark', fallback: 'Dark');
+        final tooltip = tr('ui.common.theme_toggle', fallback: '테마 전환');
+
+        if (compact) {
+          return IconButton(
+            tooltip: tooltip,
+            onPressed: () => ThemeController.instance.toggle(),
+            icon: Icon(icon),
+          );
+        }
+
+        return OutlinedButton.icon(
+          onPressed: () => ThemeController.instance.toggle(),
+          icon: Icon(icon, size: 18),
+          label: Text(label),
+        );
+      },
+    );
+  }
+}