URL previews of images, gifs, and videos should be the size of images

**Is your suggestion related to a problem? Please describe.**
GIF and image usage is currently way behind other messengers in Matrix. This makes it, quite frankly, a lot less fun and dated feeling. It is also an even bigger issues for non-techie crowds ever migrating.

**Describe the solution you'd like**
URL previews of images, gifs, and videos should be the size of images. It shouldn't matter if an image is directly uploaded into matrix or linked as an URL. Sadly it does, any external image/gif/video will have the tiny generic URL preview which is very appropriate for regular text articles if alone to make space for the text preview and because article thumbnails are generally way less important, but if it's *just* an image (direct link to image) then it is quite annoying it is impossible to see anything without a magnifier glass or clicking to expand it. It's just impossible to see anything with the current tiny image preview, so it's just quite annoying to work with.

Side note: the image preview is also just a tad too giant right now, easily taking more than half the height of my 4K screen right now on Element web. That seems like just a bit too much, something like 70% the size would work more universally I think.

**Describe alternatives you've considered**
The client could also download the URL locally and upload it into the chat, removing the technical difference. This would also be an advantage for E2E, no longer leaking previews to the home server.

**Additional context**
Add any other context or screenshots about the feature request here.