make welcome message direct

src/group_handle.rs

@@ -497,7 +497,7 @@ impl GroupHandle {
                 let post = StatusBuilder::new()
                     .status(text)
                     .content_type("text/markdown")
-                    .visibility(Visibility::Unlisted)
+                    .visibility(Visibility::Direct)
                     .build().expect("error build status");
 
                 let _ = self.client.new_status(post).await.log_error("Failed to post");