Docs: A host of corrections and improvements to inline documentation.

See #57840


git-svn-id: https://develop.svn.wordpress.org/trunk@55732 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/includes/class-wp-posts-list-table.php

@@ -651,7 +651,7 @@ class WP_Posts_List_Table extends WP_List_Table {
 	}
 
 	/**
-	 * @return array
+	 * @return string[] Array of column titles keyed by their column name.
 	 */
 	public function get_columns() {
 		$post_type = $this->screen->post_type;