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/docs/designers/language-builtin-functions/language-function-debug.md

@@ -0,0 +1,17 @@
+# {debug}
+
+`{debug}` dumps the debug console to the page. This works regardless of
+the [debug](../chapter-debugging-console.md) settings in the php script.
+Since this gets executed at runtime, this is only able to show the
+[assigned](../../programmers/api-functions/api-assign.md) variables; not the templates that are in use.
+However, you can see all the currently available variables within the
+scope of a template.
+
+If caching is enabled and a page is loaded from cache `{debug}` does
+show only the variables which assigned for the cached page.
+
+In order to see also the variables which have been locally assigned
+within the template it does make sense to place the `{debug}` tag at the
+end of the template.
+
+See also the [debugging console page](../chapter-debugging-console.md).