Certain help topics don't appear in ark's completions #959
Description
Jotting this down quickly, but ark is no help if you want to look at ?Startup, i.e. it basically fights you and tries to complete to ?packageStartupMessage or ?suppressPackageStartupMessages. Feels like our list of help completions fails to cover some category of topic. E.g. topics that aren't also exported functions or symbols.
Presumably related to / same as posit-dev/positron#6157.