fix(overview): Handle totalQuestions == 0 case

Author: pan93412

src/Controller/OverviewCardsController.php

@@ -64,6 +64,13 @@ public function level(
         $solvedQuestions = $solutionEventRepository->findSolvedQuestions($user);
         $totalQuestions = $questionRepository->count();
 
+        if (0 === $totalQuestions) {
+            return $this->render('overview/cards/level.html.twig', [
+                'level' => Level::cases()[0],
+                'rawLevelIndex' => 0,
+            ]);
+        }
+
         $solvedQuestionPercent = \count($solvedQuestions) / $totalQuestions;
         $levelIndex = ceil(\count(Level::cases()) * $solvedQuestionPercent);