Slight refactor for opening Plugins in speed dial

src/slic3r/GUI/GUI_App.cpp

@@ -8532,6 +8532,50 @@ void GUI_App::open_plugins_dialog(size_t open_on_tab, const std::string& highlig
     }
 }
 
+void GUI_App::refresh_plugins()
+{
+    // The metadata refresh blocks on disc discovery and a cloud round-trip, so run it on a worker
+    // and report completion through the notification manager -- the speed dial needs no dialog.
+    std::thread([]() {
+        refresh_plugin_metadata_blocking(/*fetch_cloud=*/true);
+        wxTheApp->CallAfter([]() {
+            if (wxGetApp().is_closing())
+                return;
+            Plater* plater = wxGetApp().plater();
+            if (plater == nullptr)
+                return;
+            plater->get_notification_manager()->push_notification(
+                NotificationType::CustomNotification,
+                NotificationManager::NotificationLevel::RegularNotificationLevel,
+                into_u8(_L("Plugins refreshed.")));
+        });
+    }).detach();
+}
+
+void GUI_App::install_local_plugin()
+{
+    if (mainframe == nullptr)
+        return;
+
+    wxFileDialog dialog(mainframe, _L("Select plugin package"), wxEmptyString, wxEmptyString, _L("Plugin files (*.py;*.whl)|*.py;*.whl"),
+                        wxFD_OPEN | wxFD_FILE_MUST_EXIST);
+    if (dialog.ShowModal() != wxID_OK)
+        return;
+
+    wxString message;
+    const bool ok = install_local_plugin_package(boost::filesystem::path(dialog.GetPath().ToUTF8().data()), mainframe, message);
+    if (message.IsEmpty())
+        return; // user cancelled the overwrite prompt
+
+    Plater* plater = this->plater();
+    if (plater == nullptr)
+        return;
+    plater->get_notification_manager()->push_notification(
+        NotificationType::CustomNotification,
+        ok ? NotificationManager::NotificationLevel::RegularNotificationLevel : NotificationManager::NotificationLevel::ErrorNotificationLevel,
+        into_u8(message));
+}
+
 void GUI_App::open_terminal_dialog()
 {
     // Reached from the plugins dialog's webview ("open_terminal" command), i.e. from