fix: allow null user type in setuser methods and improve type hinting

This commit includes changes made to both the Article.php and ArticleList.php classes in the
QUI\ERP\Accounting directory. The setUser methods now accept a null type for the 'User' parameter,
giving more flexibility when calculating user details.

Type hinting was also improved in the ArticleList class. The variable type indicators were changed
from 'int|float' to 'int | float', and from 'Factor|QUI\\ERP\\Products\\Utils\\PriceFactor' to
'Factor | QUI\\ERP\\Products\\Utils\\PriceFactor', improving readability and clarity of code.

Lastly, the 'template' and 'articleTemplate' parameters in the 'toHTMLWithCSS' method now support
both 'bool' and 'string' types, adding flexibility to template usage.

src/QUI/ERP/Accounting/Article.php

@@ -499,9 +499,9 @@ public function getUser(): ?QUI\Interfaces\Users\User
     /**
      * Set the user to the product, this user will be used for the calculation
      *
-     * @param QUI\Interfaces\Users\User $User
+     * @param null|QUI\Interfaces\Users\User $User
      */
-    public function setUser(QUI\Interfaces\Users\User $User): void
+    public function setUser(null | QUI\Interfaces\Users\User $User): void
     {
         $this->calculated = false;
         $this->User = $User;

src/QUI/ERP/Accounting/ArticleList.php

@@ -34,17 +34,17 @@ class ArticleList extends ArticleListUnique implements IteratorAggregate
     /**
      * @var int|float
      */
-    protected int|float $sum;
+    protected int | float $sum;
 
     /**
      * @var int|float
      */
-    protected int|float $grandSubSum;
+    protected int | float $grandSubSum;
 
     /**
      * @var ?QUI\Interfaces\Users\User
      */
-    protected QUI\Interfaces\Users\User|null $User = null;
+    protected QUI\Interfaces\Users\User | null $User = null;
 
     /**
      * @var ?QUI\ERP\Order\AbstractOrder
@@ -59,17 +59,17 @@ class ArticleList extends ArticleListUnique implements IteratorAggregate
     /**
      * @var int|float
      */
-    protected int|float $subSum;
+    protected int | float $subSum;
 
     /**
      * @var int|float
      */
-    protected int|float $nettoSum;
+    protected int | float $nettoSum;
 
     /**
      * @var int|float
      */
-    protected int|float $nettoSubSum;
+    protected int | float $nettoSubSum;
 
     /**
      * key 19% value[sum] = sum value[text] = text value[display_sum] formatted
@@ -140,9 +140,9 @@ public function __construct(array $attributes = [])
      * Set the user for the list
      * User for calculation
      *
-     * @param QUI\Interfaces\Users\User $User
+     * @param null|QUI\Interfaces\Users\User $User
      */
-    public function setUser(QUI\Interfaces\Users\User $User): void
+    public function setUser(null | QUI\Interfaces\Users\User $User): void
     {
         if ($this->User === $User) {
             return;
@@ -486,7 +486,7 @@ public function importPriceFactors(QUI\ERP\Accounting\PriceFactors\FactorList $P
      *
      * @throws Exception
      */
-    public function addPriceFactor(Factor|QUI\ERP\Products\Utils\PriceFactor $PriceFactor): void
+    public function addPriceFactor(Factor | QUI\ERP\Products\Utils\PriceFactor $PriceFactor): void
     {
         if ($PriceFactor instanceof QUI\ERP\Products\Utils\PriceFactor) {
             $isNetto = $this->isNetto;
@@ -550,8 +550,8 @@ public function renderForMail(): string
     }
 
     public function toHTMLWithCSS(
-        bool|string $template = false,
-        bool|string $articleTemplate = false,
+        bool | string $template = false,
+        bool | string $articleTemplate = false,
         ?QUI\Interfaces\Template\EngineInterface $Engine = null,
     ): string {
         return $this->toUniqueList()->toHTMLWithCSS($template, $articleTemplate, $Engine);