feat(material): 启用了 material 3

lib/main.dart

@@ -40,7 +40,9 @@ class Bistro extends StatelessWidget {
         colorScheme: const ColorScheme.dark(
           primary: Color(0xFFD56937),
           secondary: Color(0xFFC8C2B4),
-            background: Color(0xff384444)),
+          background: Color(0xff384444),
+        ),
+        useMaterial3 : true,
       ),
       home: const BistroFrame(
         title: '小酒馆',