Combine column from multiple rows into one row in SQLITE
You can use the GROUP_CONCAT() function:

SELECT a.Name               AS ArticleName
     , GROUP_CONCAT(t.Name) AS TagList
FROM Articles AS a
  LEFT JOIN ArticlesTags AS at
    ON at.ArticleId = a.Id
  LEFT JOIN Tags AS t
    ON t.Id = at.TagId
GROUP BY a.Id, a.Name ;