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-modifiers/language-modifier-regex-replace.md

@@ -0,0 +1,55 @@
+# regex_replace
+
+A regular expression search and replace on a variable. Use the
+[`preg_replace()`](https://www.php.net/preg_replace) syntax from the PHP
+manual.
+
+## Basic usage
+```smarty
+{$myVar|regex_replace:"/foo/":"bar"}
+```
+
+> **Note**
+>
+> Although Smarty supplies this regex convenience modifier, it is
+> usually better to apply regular expressions in PHP, either via custom
+> functions or modifiers. Regular expressions are considered application
+> code and are not part of presentation logic.
+
+## Parameters
+
+| Parameter Position | Type   | Required | Description                                    |
+|--------------------|--------|----------|------------------------------------------------|
+| 1                  | string | Yes      | This is the regular expression to be replaced. |
+| 2                  | string | Yes      | This is the string of text to replace with.    |
+
+
+## Examples
+
+```php
+<?php
+
+$smarty->assign('articleTitle', "Infertility unlikely to\nbe passed on, experts say.");
+
+```
+
+Where template is:
+
+```smarty
+{* replace each carriage return, tab and new line with a space *}
+
+{$articleTitle}
+{$articleTitle|regex_replace:"/[\r\t\n]/":" "}
+```
+       
+Will output:
+
+```
+Infertility unlikely to
+be passed on, experts say.
+Infertility unlikely to be passed on, experts say.
+```
+       
+
+See also [`replace`](language-modifier-replace.md) and
+[`escape`](language-modifier-escape.md).