Option to see the images in full screen mode and zoom in on them

[kuba-orlik]

When subscribing to an RSS feed that includes images in the content, like a webcomic, it would be super useful to be able to click on an image to see it in full screen mode and be able to zoom in and read the small text in dialog boxes

Edit: I've realized that this is the repo for the web interface and nextcloud/news-android#1367 already exists