useUserDumpFeed(): UseUserDumpFeedResult
Returns list of user userId, from GET /api/users/:userId/<list>, fetched
signed in so users see their own private dumps, with the call that loads its
next page; with categorySlug, only the dumps in that category. The socket
keeps it live: the user's new dumps come in, a dump that goes private and
public again comes back at its place, one edited out of the category
leaves, one edited into it comes in, and the upvoted list follows the
user's votes, source holding dumps at hand that a vote of theirs puts
first at once. A reconnection fetches the pages loaded again. The list and
the scroll position are saved as the page is left, under a key the overview
and the unfiltered tab share, and going back restores them.