Enhance VocabService and VocabLessonView for review lesson functionality

- Added logic in VocabService to retrieve vocabulary and lessons from previous lessons for review sessions, improving the learning experience.
- Implemented methods to gather review lessons and vocabulary exercises, ensuring users have access to relevant content during review lessons.
- Updated VocabLessonView to utilize review vocabulary exercises when in a review lesson, enhancing vocabulary extraction and user feedback.
- Improved console logging for better insights into the vocabulary processing flow, aiding in debugging and user interaction.

backend/services/vocabService.js

@@ -884,15 +884,92 @@ export default class VocabService {
     }
 
     const plainLesson = lesson.get({ plain: true });
+    
+    // Bei Wiederholungslektionen: Lade Vokabeln aus vorherigen Lektionen
+    if (plainLesson.lessonType === 'review' || plainLesson.lessonType === 'vocab_review') {
+      plainLesson.reviewLessons = await this._getReviewLessons(plainLesson.courseId, plainLesson.lessonNumber);
+      plainLesson.reviewVocabExercises = await this._getReviewVocabExercises(plainLesson.courseId, plainLesson.lessonNumber);
+    }
+    
     console.log(`[getLesson] Lektion ${lessonId} geladen:`, {
       id: plainLesson.id,
       title: plainLesson.title,
+      lessonType: plainLesson.lessonType,
       exerciseCount: plainLesson.grammarExercises ? plainLesson.grammarExercises.length : 0,
-      exercises: plainLesson.grammarExercises
+      reviewLessonsCount: plainLesson.reviewLessons ? plainLesson.reviewLessons.length : 0,
+      reviewVocabExercisesCount: plainLesson.reviewVocabExercises ? plainLesson.reviewVocabExercises.length : 0
     });
     return plainLesson;
   }
 
+  /**
+   * Sammelt alle Lektionen, die in einer Wiederholungslektion wiederholt werden sollen
+   */
+  async _getReviewLessons(courseId, currentLessonNumber) {
+    const lessons = await VocabCourseLesson.findAll({
+      where: {
+        courseId: courseId,
+        lessonNumber: {
+          [Op.lt]: currentLessonNumber // Nur Lektionen mit kleinerer Nummer
+        },
+        lessonType: {
+          [Op.notIn]: ['review', 'vocab_review'] // Keine anderen Wiederholungslektionen
+        }
+      },
+      order: [['lessonNumber', 'ASC']],
+      attributes: ['id', 'lessonNumber', 'title']
+    });
+    return lessons.map(l => l.get({ plain: true }));
+  }
+
+  /**
+   * Sammelt alle Grammatik-Übungen aus vorherigen Lektionen für Wiederholungslektionen
+   */
+  async _getReviewVocabExercises(courseId, currentLessonNumber) {
+    const previousLessons = await VocabCourseLesson.findAll({
+      where: {
+        courseId: courseId,
+        lessonNumber: {
+          [Op.lt]: currentLessonNumber
+        },
+        lessonType: {
+          [Op.notIn]: ['review', 'vocab_review']
+        }
+      },
+      attributes: ['id']
+    });
+
+    if (previousLessons.length === 0) {
+      return [];
+    }
+
+    const lessonIds = previousLessons.map(l => l.id);
+    const exercises = await VocabGrammarExercise.findAll({
+      where: {
+        lessonId: {
+          [Op.in]: lessonIds
+        }
+      },
+      include: [
+        {
+          model: VocabGrammarExerciseType,
+          as: 'exerciseType'
+        },
+        {
+          model: VocabCourseLesson,
+          as: 'lesson',
+          attributes: ['id', 'lessonNumber', 'title']
+        }
+      ],
+      order: [
+        [{ model: VocabCourseLesson, as: 'lesson' }, 'lessonNumber', 'ASC'],
+        ['exerciseNumber', 'ASC']
+      ]
+    });
+
+    return exercises.map(e => e.get({ plain: true }));
+  }
+
   async addLessonToCourse(hashedUserId, courseId, { chapterId, lessonNumber, title, description, weekNumber, dayNumber, lessonType, audioUrl, culturalNotes, targetMinutes, targetScorePercent, requiresReview }) {
     const user = await this._getUserByHashedId(hashedUserId);
     const course = await VocabCourse.findByPk(courseId);