Make citar-open more configurable

[Risto-Stevcev]

Is your feature request related to a problem? Please describe. I want to be able to get to the bibliography entry when I click on a citation or via citar-dwim or citar-open, but the menu that pops up only shows a link if there's a url associated with the bibliography entry, and/or one or more nodes if there's a node associated with the citation key. It's a common workflow to want to get to the entry, and it feels wonky to have to have a separate (citar-open-entry (citar-key-at-point)) for something like this.

Describe the solution you'd like If going to the bibtex entry were an option in the menu, I could just do citar-dwim, bind that to a key like C-c o, and then select it from the menu of actions for that citation key.

Describe alternatives you've considered Citar-embark doesn't solve the issue, because the ROAM_REFS keys are in the form of @foo @bar, which don't show up as actual highlighted links that I can click on or to C-c C-o. It does solve it sort of for [cite:@foo] links, but there's a bunch of extra stuff with embark that I don't want around because I can accidentally press a key or click on some embark menu entry that's unrelated to citar.