feat(bisaya-course): update exercise content for market-related vocabulary

- Changed the exercise question and answer to focus on market-related scenarios, replacing previous church-related content.
- Updated the explanation to align with the new vocabulary introduced in this lesson, enhancing contextual learning for students.

backend/scripts/create-bisaya-course-content.js

@@ -2490,16 +2490,16 @@ const BISAYA_EXERCISES = {
       instruction: 'Übersetze den Satz ins Bisaya.',
       questionData: {
         type: 'transformation',
-        text: 'Ich gehe in die Kirche',
+        text: 'Ich gehe später zum Markt',
         sourceLanguage: 'Deutsch',
         targetLanguage: 'Bisaya'
       },
       answerData: {
         type: 'transformation',
-        correct: 'Moadto ko sa simbahan',
+        correct: 'Moadto ko sa merkado unya',
-        alternatives: ['Adto ko sa simbahan', 'Moadto ko sa among simbahan']
+        alternatives: ['Adto ko sa merkado unya', 'Moadto ko sa merkado karon']
       },
-      explanation: '"simbahan" = Kirche.'
+      explanation: '"Moadto ko sa merkado unya" passt zum in dieser Lektion eingeführten Alltagswortschatz rund um Wege und Markt.'
     }
   ],