Categories refactor (#9233)

* feat: wip categories pagination

* feat: add subCategoriesPerPage setting

* feat: add load more sub categories button to category page

* fix: openapi spec

* feat: show sub categories left on category page

hide button when no more categories left

* breaking: rename categories to allCategories on /search

categories contains the search results

* fix: spec

* refactor: remove cidsPerPage

* fix: tests

* feat: use component for subcategories

* fix: prevent negative subCategoriesLeft

src/categories/data.js

@@ -10,7 +10,7 @@ const utils = require('../utils');
 const intFields = [
 	'cid', 'parentCid', 'disabled', 'isSection', 'order',
 	'topic_count', 'post_count', 'numRecentReplies',
-	'minTags', 'maxTags', 'postQueue',
+	'minTags', 'maxTags', 'postQueue', 'subCategoriesPerPage',
 ];
 
 module.exports = function (Categories) {