fix(phpstan): remove unreachable branches and add method existence checks

This commit removes unreachable 'else' branches and irrelevant PHPStan error messages from the
PHPStan configuration file. It also updates the `InvoiceView` and `OutputProviderInvoice` classes
to add checks for the existence of methods before invoking them. This prevents runtime errors in
cases where the methods do not exist.

Related: #153

phpstan-baseline.neon

@@ -55,26 +55,6 @@ parameters:
 			count: 2
 			path: src/QUI/ERP/Accounting/Invoice/InvoiceTemporary.php
 
-		-
-			message: "#^Else branch is unreachable because previous condition is always true\\.$#"
-			count: 1
-			path: src/QUI/ERP/Accounting/Invoice/InvoiceView.php
-
-		-
-			message: "#^Unreachable statement \\- code above always terminates\\.$#"
-			count: 1
-			path: src/QUI/ERP/Accounting/Invoice/InvoiceView.php
-
-		-
-			message: "#^Call to an undefined method QUI\\\\ERP\\\\Accounting\\\\ArticleListUnique\\:\\:setUser\\(\\)\\.$#"
-			count: 1
-			path: src/QUI/ERP/Accounting/Invoice/Output/OutputProviderInvoice.php
-
-		-
-			message: "#^Call to an undefined method QUI\\\\ERP\\\\Accounting\\\\ArticleListUnique\\:\\:toUniqueList\\(\\)\\.$#"
-			count: 1
-			path: src/QUI/ERP/Accounting/Invoice/Output/OutputProviderInvoice.php
-
 		-
 			message: "#^Call to static method getInstance\\(\\) on an unknown class QUI\\\\ERP\\\\Order\\\\Handler\\.$#"
 			count: 1

src/QUI/ERP/Accounting/Invoice/InvoiceView.php

@@ -33,18 +33,10 @@ class InvoiceView extends QUI\QDOM
      * InvoiceView constructor.
      *
      * @param Invoice|InvoiceTemporary $Invoice
-     *
-     * @throws Exception
      */
     public function __construct(Invoice | InvoiceTemporary $Invoice)
     {
-        if ($Invoice instanceof Invoice || $Invoice instanceof InvoiceTemporary) {
-            $this->Invoice = $Invoice;
-
-            return;
-        }
-
-        throw new Exception('$Invoice must be an instance of Invoice or InvoiceTemporary');
+        $this->Invoice = $Invoice;
     }
 
     /**
@@ -308,7 +300,11 @@ class_exists('QUI\ERP\Accounting\Payments\Methods\AdvancePayment\Payment')
                 } else {
                     $timeForPayment = $Locale->get('quiqqer/invoice', 'additional.invoice.text.timeForPayment.0');
                 }
-            } else {
+            }
+
+            /*
+             // Else is unreachable because previous condition is always true.
+             else {
                 $timeForPayment = strtotime($timeForPayment);
 
                 if (date('Y-m-d') === date('Y-m-d', $timeForPayment)) {
@@ -317,6 +313,7 @@ class_exists('QUI\ERP\Accounting\Payments\Methods\AdvancePayment\Payment')
                     $timeForPayment = $Formatter->format($timeForPayment);
                 }
             }
+            */
 
             return $Locale->get(
                 'quiqqer/invoice',

src/QUI/ERP/Accounting/Invoice/Output/OutputProviderInvoice.php

@@ -168,8 +168,13 @@ public static function getTemplateData(int | string $entityId): array
         $Articles = $Invoice->getArticles();
 
         if (get_class($Articles) !== QUI\ERP\Accounting\ArticleListUnique::class) {
-            $Articles->setUser($Customer);
-            $Articles = $Articles->toUniqueList();
+            if (method_exists($Articles, 'setUser')) {
+                $Articles->setUser($Customer);
+            }
+
+            if (method_exists($Articles, 'toUniqueList')) {
+                $Articles = $Articles->toUniqueList();
+            }
         }
 
         // Delivery address