Dev-Umgebung: Kompatibilität für PHP 8.3 + Smarty 4.5.6

- Smarty 4.1.1 → 4.5.6 (behebt dynamic property deprecations)
- Core-Klassen: #[\AllowDynamicProperties] für Admin_role, base, Config,
  Customer, Customer_group, CustomerGroups, Item, Structure, website
- website.class.php: counts[parent_id] initialisieren vor ++ (PHP 8.1)
- layout.class.php: HTTP_ACCEPT_LANGUAGE mit isset-Guard
- website_init.php: session_status()-Check vor session_start
- .htaccess: HTTPS-Redirect via X-Forwarded-Proto (statt SERVER_PORT)
- themes/easyshop_advanced/media/: Parent-Theme-Assets nachgezogen
- .gitignore: smarty.4.1.1.bak ausschließen

libs/smarty/run-tests.sh

@@ -0,0 +1,10 @@
+#!/bin/sh
+
+# Runs composer update, echoes php version and runs PHPUnit
+# Usage examples:
+# - ./run-tests.sh --group 20221124
+# - ./run-tests.sh --exclude-group slow
+
+composer update --quiet
+#php -r 'echo "\nPHP version " . phpversion() . ". ";'
+php ./vendor/phpunit/phpunit/phpunit $@