refactor: remove forum and topic feature chains

inc/helpers/homepage/header-components.php

@@ -16,7 +16,6 @@ if (!function_exists('aksrt_header_components_page_type_keys')) {
 	function aksrt_header_components_page_type_keys(): array {
 		return [
 			'home',
-			'topics',
 			'category',
 			'tag',
 			'author',
@@ -68,11 +67,6 @@ if (!function_exists('aksrt_header_slide_match_page_type')) {
 			$post_type = (string) $raw_post_type;
 		}
 
-		// Special keys that are not plain is_{$type} flags.
-		if ($type === 'topics') {
-			return is_tax('topics');
-		}
-
 		// Generic WP_Query is_* flags (home/category/tag/author/single/search/page).
 		$query_flag = 'is_' . $type;
 		if (empty($wp_query->{$query_flag})) {