Add Czech translation

common.php

@@ -43,6 +43,7 @@ header("Cross-Origin-Opener-Policy: same-origin");
 header("Cross-Origin-Resource-Policy: same-origin");
 
 const LANGUAGES = [
+	'cs' => ['name' => 'čeština', 'locale' => 'cs_CZ', 'flag' => '🇨🇿', 'show_in_menu' => true, 'dir' => 'ltr'],
 	'de' => ['name' => 'Deutsch', 'locale' => 'de_DE', 'flag' => '🇩🇪', 'show_in_menu' => true, 'dir' => 'ltr'],
 	'en' => ['name' => 'English', 'locale' => 'en_GB', 'flag' => '🇬🇧', 'show_in_menu' => true, 'dir' => 'ltr'],
 	'ru' => ['name' => 'Русский', 'locale' => 'ru_RU', 'flag' => '🇷🇺', 'show_in_menu' => true, 'dir' => 'ltr'],