feat: product search on TYPO3 13

Search page (searchresult plugin), AJAX results and filter panel, the
mobile filter overlay, search links ("Alle anzeigen", menu icon) and
the /reiseauswahl/{name} landing redirects are back. The search bar in
the page header stays out (SearchbarController not ported); on detail
pages the menu icon links to the search page instead of toggling it.

- Extbase requests are immutable: withArgument() instead of
  setArgument()
- StaticSearchParamsMiddleware runs after site resolution and before
  page resolution (the old position is a cycle in v13); FilterService
  copes with the missing TypoScript there, as TYPO3 10 did
- Search and filter forms are sent URL-encoded instead of multipart, so
  production can keep rejecting multipart requests
- ski-wochenenden: websiteTitle from the old sys_template sitetitle

Compared with TYPO3 10 on the same data (249 cases: search pages with
all 41 preset filters, landing redirects, AJAX results and filter
panel, GET and POST): 186 identical, 63 with the same results in a
different order (PHP 8 sorts stably, ties came out in arbitrary order
on PHP 7.4). Processed image names differ by their configuration hash.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

packages/ep_theme/Classes/ViewHelpers/PriceRangeViewHelper.php

@@ -0,0 +1,59 @@
+<?php
+
+namespace EP\EpTheme\ViewHelpers;
+
+/***************************************************************
+ *
+ *  Copyright notice
+ *
+ *  (c) 2021 Björn Fromme <[email protected]>, dreipunktnull
+ *
+ *  All rights reserved
+ *
+ *  This script is part of the TYPO3 project. The TYPO3 project is
+ *  free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  The GNU General Public License can be found at
+ *  http://www.gnu.org/copyleft/gpl.html.
+ *
+ *  This script is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  This copyright notice MUST APPEAR in all copies of the script!
+ ***************************************************************/
+
+use TYPO3Fluid\Fluid\Core\Rendering\RenderingContextInterface;
+use TYPO3Fluid\Fluid\Core\ViewHelper\AbstractViewHelper;
+
+class PriceRangeViewHelper extends AbstractViewHelper
+{
+    public function initializeArguments()
+    {
+        parent::initializeArguments();
+
+        $this->registerArgument('min', 'mixed', 'Price range start');
+        $this->registerArgument('max', 'mixed', 'Price range end');
+    }
+
+    /**
+     * @param array $arguments
+     * @param \Closure $renderChildrenClosure
+     * @param RenderingContextInterface $renderingContext
+     * @return mixed
+     */
+    public function render()
+    {
+        if (1 === (int) $this->arguments['min']) {
+            return sprintf('bis %d €', $this->arguments['max']);
+        }
+        if (999 === (int) $this->arguments['max']) {
+            return sprintf('ab %d €', $this->arguments['min']);
+        }
+        return sprintf('%d bis %d €', $this->arguments['min'], $this->arguments['max']);
+    }
+}