As a query writer
I want to filter my results for the existence of an article on a particular Wikimedia project
in order to find articles that need to be written still

Problem:
Right now the Query Builder does not allow you to filter based on if a sitelink to a particular project exists or not.

Example:

Screenshots/mockups:

BDD
GIVEN
AND
WHEN
AND
THEN
AND

Acceptance criteria:

Original request:

• https://www.wikidata.org/wiki/Wikidata_talk:Query_Builder#A_simple_and_clear_way_to_show_items_without_Wikipedia_articles_+_convert_to_Listeria_list_button_or_instructions