Add grammar exercise creation in course generation

- Integrated functionality to create example grammar exercises for grammar lessons during course creation.
- Added a new helper function to generate gap fill and multiple choice exercises based on lesson data.
- Enhanced logging to confirm the number of grammar exercises created, improving feedback during course setup.

backend/scripts/create-language-courses.js

@@ -15,6 +15,7 @@
 import { sequelize } from '../utils/sequelize.js';
 import VocabCourse from '../models/community/vocab_course.js';
 import VocabCourseLesson from '../models/community/vocab_course_lesson.js';
+import VocabGrammarExercise from '../models/community/vocab_grammar_exercise.js';
 import User from '../models/community/user.js';
 import crypto from 'crypto';
 import bcrypt from 'bcryptjs';
@@ -330,8 +331,9 @@ async function createCourseForLanguage(targetLanguageId, nativeLanguageId, langu
   console.log(`   ✅ Kurs erstellt: "${course.title}" (ID: ${course.id}, Share-Code: ${shareCode})`);
 
   // Erstelle Lektionen
+  const createdLessons = [];
   for (const lessonData of LESSON_TEMPLATE) {
-    await VocabCourseLesson.create({
+    const lesson = await VocabCourseLesson.create({
       courseId: course.id,
       chapterId: null,
       lessonNumber: lessonData.num,
@@ -345,12 +347,78 @@ async function createCourseForLanguage(targetLanguageId, nativeLanguageId, langu
       targetScorePercent: lessonData.targetScore,
       requiresReview: lessonData.review
     });
+    createdLessons.push({ lesson, lessonData });
   }
 
   console.log(`   ✅ ${LESSON_TEMPLATE.length} Lektionen erstellt`);
+
+  // Erstelle Beispiel-Grammatik-Übungen für Grammar-Lektionen
+  let grammarExerciseCount = 0;
+  for (const { lesson, lessonData } of createdLessons) {
+    if (lessonData.type === 'grammar') {
+      // Erstelle 2-3 Beispiel-Übungen für jede Grammar-Lektion
+      const exercises = createExampleGrammarExercises(lesson.id, lessonData, ownerUserId);
+      for (const exercise of exercises) {
+        await VocabGrammarExercise.create(exercise);
+        grammarExerciseCount++;
+      }
+    }
+  }
+
+  if (grammarExerciseCount > 0) {
+    console.log(`   ✅ ${grammarExerciseCount} Grammatik-Übungen erstellt`);
+  }
+
   return course;
 }
 
+// Erstelle Beispiel-Grammatik-Übungen für eine Grammar-Lektion
+function createExampleGrammarExercises(lessonId, lessonData, ownerUserId) {
+  const exercises = [];
+  
+  // Beispiel-Übung 1: Gap Fill (Lückentext)
+  exercises.push({
+    lessonId: lessonId,
+    exerciseTypeId: 1, // gap_fill
+    exerciseNumber: 1,
+    title: `${lessonData.title} - Übung 1`,
+    instruction: 'Fülle die Lücken mit den richtigen Wörtern.',
+    questionData: JSON.stringify({
+      type: 'gap_fill',
+      text: 'Hallo! Wie geht es {gap}? Mir geht es {gap}, danke!',
+      gaps: 2
+    }),
+    answerData: JSON.stringify({
+      type: 'gap_fill',
+      answers: ['dir', 'gut']
+    }),
+    explanation: 'Die richtigen Antworten sind "dir" und "gut".',
+    createdByUserId: ownerUserId
+  });
+
+  // Beispiel-Übung 2: Multiple Choice
+  exercises.push({
+    lessonId: lessonId,
+    exerciseTypeId: 2, // multiple_choice
+    exerciseNumber: 2,
+    title: `${lessonData.title} - Übung 2`,
+    instruction: 'Wähle die richtige Antwort aus.',
+    questionData: JSON.stringify({
+      type: 'multiple_choice',
+      question: 'Wie sagt man "Guten Tag" auf ' + lessonData.title.split(' - ')[0] + '?',
+      options: ['Option A', 'Option B', 'Option C', 'Option D']
+    }),
+    answerData: JSON.stringify({
+      type: 'multiple_choice',
+      correctAnswer: 0
+    }),
+    explanation: 'Die richtige Antwort ist Option A.',
+    createdByUserId: ownerUserId
+  });
+
+  return exercises;
+}
+
 async function findOrCreateSystemUser() {
   // Versuche zuerst einen System-Benutzer zu finden (z.B. mit username "system" oder "admin")
   let systemUser = await User.findOne({