Docs: Docs on docs. Further improve documentation of known return types, plus other docs fixes.

See #48303


git-svn-id: https://develop.svn.wordpress.org/trunk@46662 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/taxonomy.php

@@ -73,7 +73,7 @@ function wp_create_category( $cat_name, $parent = 0 ) {
  *
  * @param string[] $categories Array of category names to create.
  * @param int      $post_id    Optional. The post ID. Default empty.
- * @return array List of categories to create for the given post.
+ * @return int[] Array of IDs of categories assigned to the given post.
  */
 function wp_create_categories( $categories, $post_id = '' ) {
 	$cat_ids = array();