CodeIgniter 3.1.11 -> 3.4.5 (pocketarc fork) en PHP 8.3-fixes

- system/ vervangen door CodeIgniter 3.4.5 (pocketarc/codeigniter, PHP 8.2-8.5 compatibel)
- config.php, mimes.php, user_agents.php en error-views bijgewerkt naar 3.4.5
- composer.json: php-constraint "^7.4 || ^8.0" zodat composer install op 8.3 werkt
- PHP 8-fatals opgelost: count()/array-functies op FALSE/null, rekenen met lege
  strings, delen door nul, property zetten op FALSE, curly-brace string offsets,
  ongedefinieerde constanten, foute curl_setopt in Phantom_model::create_img
- dynamic properties gedeclareerd in libraries, optionele parameters voor verplichte opgelost
- vergelijkingen waar '' == 0 in PHP 8 anders uitvalt gecast naar (int)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

system/helpers/date_helper.php

@@ -6,7 +6,7 @@
  *
  * This content is released under the MIT License (MIT)
  *
- * Copyright (c) 2014 - 2019, British Columbia Institute of Technology
+ * Copyright (c) 2019 - 2022, CodeIgniter Foundation
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
@@ -30,6 +30,7 @@
  * @author	EllisLab Dev Team
  * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
  * @copyright	Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/)
+ * @copyright	Copyright (c) 2019 - 2022, CodeIgniter Foundation (https://codeigniter.com/)
  * @license	https://opensource.org/licenses/MIT	MIT License
  * @link	https://codeigniter.com
  * @since	Version 1.0.0
@@ -44,7 +45,7 @@ defined('BASEPATH') OR exit('No direct script access allowed');
  * @subpackage	Helpers
  * @category	Helpers
  * @author		EllisLab Dev Team
- * @link		https://codeigniter.com/user_guide/helpers/date_helper.html
+ * @link		https://codeigniter.com/userguide3/helpers/date_helper.html
  */
 
 // ------------------------------------------------------------------------
@@ -130,14 +131,10 @@ if ( ! function_exists('standard_date'))
 	 * Returns a date formatted according to the submitted standard.
 	 *
 	 * As of PHP 5.2, the DateTime extension provides constants that
-	 * serve for the exact same purpose and are used with date().
+	 * serve for the exact same purpose and are used internally by
+	 * date() as well.
 	 *
-	 * @todo	Remove in version 3.1+.
-	 * @deprecated	3.0.0	Use PHP's native date() instead.
-	 * @link	http://www.php.net/manual/en/class.datetime.php#datetime.constants.types
-	 *
-	 * @example	date(DATE_RFC822, now()); // default
-	 * @example	date(DATE_W3C, $time); // a different format and time
+	 * @deprecated	3.1.3	Use PHP's native date() with DateTime constants
 	 *
 	 * @param	string	$fmt = 'DATE_RFC822'	the chosen format
 	 * @param	int	$time = NULL		Unix timestamp
@@ -606,7 +603,7 @@ if ( ! function_exists('timezones'))
 	 * for various other ones in this library
 	 *
 	 * @param	string	timezone
-	 * @return	string
+	 * @return	string|array
 	 */
 	function timezones($tz = '')
 	{