Add topic name (or alias?) to dropdown of recently-viewed R help

As you view various R help topics, the help pane has a dropdown menu that allows you to easily navigate back to them. Here I've done

?toupper()
?lapply()

And here's what that dropdown looks like:

I think we need to include the topic here to make it actually useful, i.e. the user should see "toupper" (well, see next paragraph) and "lapply". This should probably happen even at the cost of showing less of the topic's title ("Character Translation and Case Folding" and "Apply a Function over a List or Vector", in this example). It's conceivable that we should not show the title at all.

As for showing the user what they searched for help on, it's not quite as simple as displaying the topic ("foofy" when showing the help in "foofy.Rd"), because you can document multiple things in 1 topic, but the topic can obviously have only 1 name. So the topic title associated with ?toupper is actually chartr, which won't mean anything to a person who looked up ?toupper. That has to be finessed. I'm sure it's easiest to show chartr, but it might be nice to show the alias (?toupper in this example) that the user asked for, if possible.

No file, test, or entry point is identified in the issue. Start by locating the recently-viewed R help dropdown implementation and trace how a searched alias and its topic title are retained. Done means the dropdown makes recently viewed topics identifiable while handling cases where the searched alias differs from the topic name.