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-nl2br.md

@@ -0,0 +1,37 @@
+# nl2br
+
+All `"\n"` line breaks will be converted to html `<br />` tags in the
+given variable. This is equivalent to the PHP\'s
+[`nl2br()`](https://www.php.net/nl2br) function.
+
+## Basic usage
+```smarty
+{$myVar|nl2br}
+```
+
+## Examples
+
+```php
+<?php
+
+$smarty->assign('articleTitle',
+                "Sun or rain expected\ntoday, dark tonight"
+                );
+
+```
+
+Where the template is:
+
+```smarty
+{$articleTitle|nl2br}
+```
+       
+Will output:
+
+```
+Sun or rain expected<br />today, dark tonight
+```
+
+See also [`word_wrap`](language-modifier-wordwrap.md),
+[`count_paragraphs`](language-modifier-count-paragraphs.md) and
+[`count_sentences`](language-modifier-count-sentences.md).