Lightbox issues & improvements

```[tasklist]
### Bugs
- [ ] #10089
- [ ] https://github.com/guardian/dotcom-rendering/issues/10322
- [ ] All images are eagerly loaded on Firefox
- [ ] No previous/next button for a single image
- [ ] Reinstate previous/next for Cartoon/Picture series [frontend PR#20462]
- [ ] Lightbox not available after clicking New updates live blog toast (for new blocks appearing without page reload too)
- [ ] https://github.com/guardian/dotcom-rendering/issues/10922
- [x] Lightbox doesn’t work in [keyTakeaway](https://www.theguardian.com/sport/article/2024/aug/13/paris-olympics-2024-australlia-best-athletes-to-watch-brisbane-2032), [QandA](https://www.theguardian.com/science/article/2024/aug/19/what-is-blue-supermoon-when-uk-skies#how-rare-is-a-blue-supermoon) and (possibly other) template(s)
```

### Health
- [ ] [Stop debouncing](https://developer.mozilla.org/en-US/docs/Web/API/Document/scroll_event)
- [ ] Remove initialisation method in favour of state
- [ ] Make defer until hash take a startWith parameter
- [ ] Consider rendering images on the server, it's only a few kB gzipped
- [ ] Consider using the `dialog` element
- [ ] Investigate if we can make it faster!

```[tasklist]
### Improvements
- [ ] https://github.com/guardian/dotcom-rendering/issues/11879
- [ ] Allow zooming (pinch and double tap/click)
- [ ] Check if spinner loader doesn’t annul JPEG [XL] progressive image loading
```