Make image carousel dots bigger

### Problem I have

I use Phanpy for a Pixelfed account as well as for a Mastodon account. The multi-image carousel dots in my Pixelfed feed are so tiny by default that I kept not noticing when posts have multiple images. They seem really disproportionate.

### Solution I'd like

Would it be possible to enlarge these dots, or to make the size configurable?

### Alternatives considered

My workaround is a user style that enlarges them from 5px to 15px, which I find much more usable -- I haven't missed a multi-image post since I enabled this:

### Other

_No response_