feat(vocab): add language and course dictionary endpoints and UI components

- Implemented `getLanguageDictionary` and `getCourseDictionary` methods in the VocabService to retrieve vocabulary entries filtered by search terms.
- Updated VocabController and vocabRouter to include new routes for accessing language and course dictionaries.
- Enhanced frontend components to navigate to the new dictionary views, including buttons in VocabCourseView and VocabLanguageView.
- Added localization entries for the dictionary feature in multiple languages, ensuring a consistent user experience across the platform.

backend/services/vocabService.js

@@ -1605,6 +1605,64 @@ export default class VocabService {
     return { languageId: access.id, results: rows };
   }
 
+  /**
+   * Wörterbuch: alle Vokabeln einer Trainer-Sprache (Kapitel), optional gefiltert.
+   * Ein Suchbegriff durchsucht Lern- und Referenzspalte (Teilstrings, ILIKE).
+   */
+  async getLanguageDictionary(hashedUserId, languageId, { q } = {}) {
+    const user = await this._getUserByHashedId(hashedUserId);
+    const access = await this._getLanguageAccess(user.id, languageId);
+    const term = typeof q === 'string' ? q.trim() : '';
+    const like = term ? `%${term}%` : null;
+
+    const rows = await sequelize.query(
+      `
+      SELECT
+        cl.id,
+        c.id AS "chapterId",
+        c.title AS "chapterTitle",
+        l1.text AS "learning",
+        l2.text AS "reference"
+      FROM community.vocab_chapter_lexeme cl
+      JOIN community.vocab_chapter c ON c.id = cl.chapter_id
+      JOIN community.vocab_lexeme l1 ON l1.id = cl.learning_lexeme_id
+      JOIN community.vocab_lexeme l2 ON l2.id = cl.reference_lexeme_id
+      WHERE c.language_id = :languageId
+        ${like ? 'AND (l1.text ILIKE :like OR l2.text ILIKE :like)' : ''}
+      ORDER BY c.title ASC, l1.text ASC, l2.text ASC
+      LIMIT 20000
+      `,
+      {
+        replacements: like ? { languageId: access.id, like } : { languageId: access.id },
+        type: sequelize.QueryTypes.SELECT,
+      }
+    );
+
+    return { languageId: access.id, results: rows };
+  }
+
+  /**
+   * Wörterbuch: aus abgeschlossenen Kurslektionen extrahierte Paare, optional gefiltert (Teilstring in beiden Spalten).
+   */
+  async getCourseDictionary(hashedUserId, courseId, { q } = {}) {
+    const pool = await this.getCompletedLessonVocabPool(hashedUserId, courseId);
+    const term = typeof q === 'string' ? q.trim().toLowerCase() : '';
+    let vocabs = pool.vocabs || [];
+    if (term) {
+      vocabs = vocabs.filter((entry) => {
+        const l = String(entry.learning || '').toLowerCase();
+        const r = String(entry.reference || '').toLowerCase();
+        return l.includes(term) || r.includes(term);
+      });
+    }
+    vocabs.sort((a, b) => {
+      const refCmp = String(a.reference || '').localeCompare(String(b.reference || ''), undefined, { sensitivity: 'base' });
+      if (refCmp !== 0) return refCmp;
+      return String(a.learning || '').localeCompare(String(b.learning || ''), undefined, { sensitivity: 'base' });
+    });
+    return { courseId: pool.courseId, results: vocabs };
+  }
+
   async addVocabToChapter(hashedUserId, chapterId, { learning, reference }) {
     const user = await this._getUserByHashedId(hashedUserId);
     const ch = await this._getChapterAccess(user.id, chapterId);