merge: add website link in about screen

lib/screens/about_screen.dart

@@ -13,6 +13,7 @@ class AboutScreen extends StatefulWidget {
 
 class _AboutScreenState extends State<AboutScreen> {
   static const _supportEmail = 'support@car64.app';
+  static const _websiteUrl = 'https://www.car64.app/';
 
   PackageInfo? _packageInfo;
 
@@ -46,6 +47,18 @@ class _AboutScreenState extends State<AboutScreen> {
     }
   }
 
+  Future<void> _openWebsite() async {
+    final uri = Uri.parse(_websiteUrl);
+    final launched = await launchUrl(uri, mode: LaunchMode.externalApplication);
+    if (!launched && mounted) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        const SnackBar(
+          content: Text('Could not open website. Please visit https://www.car64.app/'),
+        ),
+      );
+    }
+  }
+
   @override
   Widget build(BuildContext context) {
     final theme = Theme.of(context);
@@ -139,6 +152,16 @@ class _AboutScreenState extends State<AboutScreen> {
           ),
 
           const SizedBox(height: 20),
+          SizedBox(
+            width: double.infinity,
+            child: OutlinedButton.icon(
+              onPressed: _openWebsite,
+              icon: const Icon(Icons.language),
+              label: const Text('Visit Website'),
+            ),
+          ),
+
+          const SizedBox(height: 10),
           SizedBox(
             width: double.infinity,
             child: OutlinedButton.icon(