message: fix: overlay layout for `Responsive`
diff: @@ -178,7 +178,7 @@ where
  let content_layout = state.layout(layout);
  match content {
  - Content::Pending(_) => false,
  + Content::Pending(_) => None,
  Content::Ready(cache) => {
  *cache = Some(
  CacheBuilder {
  @@ -190,14 +190,19 @@ where
  .build(),
  );
  - cache.as_ref().unwrap().borrow_overlay().is_some()
  + cache
  + .as_ref()
  + .unwrap()
  + .borrow_overlay()
  + .as_ref()
  + .map(|overlay| overlay.position())
  }
  }
  };
  - has_overlay.then(|| {
  + has_overlay.map(|position| {
  overlay::Element::new(
  - layout.position(),
  + position,
  Box::new(Overlay { instance: self }),
  )
  })
  