fix: Uri.toString() for "mailto" does not encode spaces properly

dart-lang/sdk#43838

Author: thibaultzanini

packages/core/lib/logic/services/messenger.service.dart

@@ -5,6 +5,13 @@ import 'package:url_launcher/url_launcher_string.dart';
 
 /// A class representing a fast messenger.
 class FastMessenger {
+  static String? encodeQueryParameters(Map<String, String> params) {
+    return params.entries
+        .map((MapEntry<String, String> e) =>
+            '${Uri.encodeComponent(e.key)}=${Uri.encodeComponent(e.value)}')
+        .join('&');
+  }
+
   static Future<void> writeEmail(
     String recipientEmail, {
     String? subject,
@@ -13,10 +20,10 @@ class FastMessenger {
     final Uri uri = Uri(
       scheme: 'mailto',
       path: recipientEmail,
-      queryParameters: <String, String>{
+      query: encodeQueryParameters(<String, String>{
         if (subject != null) 'subject': subject,
         if (body != null) 'body': body,
-      },
+      }),
     );
 
     return launchUrl(uri.toString());