Guest favorites

**Is your feature request related to a problem? Please describe.**
I generally like to lurk and browse without logging in. As far as I can tell, Voyager doesn’t have a feature that allows an anonymous user to compile and quickly access a saved list of communities. Currently, you have to either scroll through the list of communities in the Posts tab, or search for it in the Search tab.

**Describe the solution you'd like**
If possible, it would be nice to have a “Bookmarks” feature: essentially just a list of communities a user has saved to quickly jump to. It wouldn’t necessarily have to aggregate the content, like Subscribe/Favorite, but simply act as a quick navigational feature.

**Describe alternatives you've considered**
Ultimately, this may be superficially similar to or the same as #934, but I’m not sure.

**Additional context**
Thank you for this great app and all of the effort you’ve put into making Lemmy easily accessible!