send preferred_buffer_scale event after entering an output

Qt 6.7.0+ requires this to correctly scale when fractional scale is not
enabled.

src/view/wlr-surface-node.cpp

@@ -486,6 +486,7 @@ void wf::scene::wlr_surface_node_t::update_pending_outputs()
             {
                 wlr_surface_send_enter(surface, wo->handle);
                 wlr_fractional_scale_v1_notify_scale(surface, wo->handle->scale);
+                wlr_surface_set_preferred_buffer_scale(surface, wo->handle->scale);
             }
         } else if (delta < 0)
         {