feat: Status-Pipeline (reviewed), Audio-Verknüpfung+Coverage, EP-Fortschritt, Wort-Generierung

- reviewed-Status für objects/questions/statements/pairs (Constraints)
- feed: nur fertige Inhalte (published + Bild + Audio-Gate), audio_url
- pairs: Publish-Gating (draft→published = 409)
- audios: source_table/source_id/source_field/language + Unique-Index;
  generate-for, generate-batch, GET /coverage; voices.js (Voice je Sprache)
- auth: POST /auth/progress, /auth/me mit total_ep/streak/level;
  users_public EP-Spalten + user_pair_progress.earned_points
- claude: POST /generate-words; words POST akzeptiert status

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/routes/words.js

@@ -45,11 +45,13 @@ router.get('/', async (req, res, next) => {
 // POST /api/words
 router.post('/', async (req, res, next) => {
   try {
-    const { titel_de, titel_en, titel_sv, difficulty_level } = req.body;
+    const { titel_de, titel_en, titel_sv, difficulty_level, status } = req.body;
+    if (status && !STATUSES.includes(status))
+      return res.status(400).json({ error: `status must be one of: ${STATUSES.join(', ')}` });
     const result = await query(
-      `INSERT INTO words (titel_de, titel_en, titel_sv, difficulty_level, requested_at)
-       VALUES ($1, $2, $3, $4, NOW()) RETURNING *`,
-      [titel_de || null, titel_en || null, titel_sv || null, difficulty_level || null]
+      `INSERT INTO words (titel_de, titel_en, titel_sv, difficulty_level, status, requested_at)
+       VALUES ($1, $2, $3, $4, COALESCE($5, 'requested'), NOW()) RETURNING *`,
+      [titel_de || null, titel_en || null, titel_sv || null, difficulty_level || null, status || null]
     );
     res.status(201).json({ ...result.rows[0], picture_ids: [], category_ids: [] });
   } catch (err) { next(err); }