DONE: generate letter after the membership-application is completed

be/app/Services/LetterService.php

@@ -33,7 +33,7 @@ class LetterService
      */
     public function pdfResponse(string $view, array $data = [], string $filename = 'letter.pdf'): Response
     {
-        $pdf = $this->makeBrowsershot($this->renderHtml($view, $data))->pdf();
+        $pdf = $this->renderPdf($view, $data);
 
         return response($pdf, SymfonyResponse::HTTP_OK, [
             'Content-Type' => 'application/pdf',
@@ -41,6 +41,14 @@ class LetterService
         ]);
     }
 
+    /**
+     * @param  array<string, mixed>  $data
+     */
+    public function renderPdf(string $view, array $data = []): string
+    {
+        return $this->makeBrowsershot($this->renderHtml($view, $data))->pdf();
+    }
+
     /**
      * @param  array<string, mixed>  $overrides
      * @return array<string, mixed>