Add missing relation endpoints for content_mentor migration

- GET /api/objects?picture_id=X filter via object_pictures join
- GET /api/objects/:id/words — full word details
- GET /api/objects/:id/pairs — pairs with nested question + statements
- GET /api/words?titel_de=X case-insensitive filter
- GET /api/pictures/:id/words — full word details
- DELETE /api/pictures/:id/words/:wordId — convenience unlink

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/routes/objects.js

@@ -28,10 +28,13 @@ async function getWithRelations(id) {
 // GET /api/objects
 router.get('/', async (req, res, next) => {
   try {
-    const { status, limit = 50, offset = 0 } = req.query;
+    const { status, picture_id, limit = 50, offset = 0 } = req.query;
     const params = [Math.min(parseInt(limit), 500), parseInt(offset)];
-    const where = status ? `WHERE o.status = $3` : '';
+    const conditions = [];
-    if (status) params.push(status);
+    if (status) { conditions.push(`o.status = $${params.length + 1}`); params.push(status); }
+    if (picture_id) { conditions.push(`op2.picture_id = $${params.length + 1}`); params.push(picture_id); }
+    const where = conditions.length ? `WHERE ${conditions.join(' AND ')}` : '';
+    const join2 = picture_id ? `LEFT JOIN object_pictures op2 ON op2.object_id = o.id` : '';
     const result = await query(
       `SELECT o.*,
         COALESCE(json_agg(DISTINCT ow.word_id)    FILTER (WHERE ow.word_id    IS NOT NULL), '[]') AS word_ids,
@@ -41,6 +44,7 @@ router.get('/', async (req, res, next) => {
        LEFT JOIN object_words    ow  ON ow.object_id  = o.id
        LEFT JOIN object_pictures op  ON op.object_id  = o.id
        LEFT JOIN object_pairs    opr ON opr.object_id = o.id
+       ${join2}
        ${where}
        GROUP BY o.id
        ORDER BY o.created_at DESC
@@ -110,6 +114,69 @@ router.delete('/:id', async (req, res, next) => {
   } catch (err) { next(err); }
 });
 
+// --- Relation detail reads ---
+
+// GET /api/objects/:id/words  — full word objects
+router.get('/:id/words', async (req, res, next) => {
+  try {
+    const result = await query(
+      `SELECT w.* FROM words w
+       JOIN object_words ow ON ow.word_id = w.id
+       WHERE ow.object_id = $1
+       ORDER BY w.created_at DESC`,
+      [req.params.id]
+    );
+    res.json(result.rows);
+  } catch (err) { next(err); }
+});
+
+// GET /api/objects/:id/pairs  — full pair objects with nested question + statements
+router.get('/:id/pairs', async (req, res, next) => {
+  try {
+    const pairsResult = await query(
+      `SELECT p.* FROM pairs p
+       JOIN object_pairs op ON op.pair_id = p.id
+       WHERE op.object_id = $1
+       ORDER BY p.created_at DESC`,
+      [req.params.id]
+    );
+    const pairs = pairsResult.rows;
+    if (!pairs.length) return res.json([]);
+
+    // Fetch linked questions and statements in bulk
+    const qIds = [...new Set(pairs.map(p => p.question_id).filter(Boolean))];
+    const posIds = [...new Set(pairs.map(p => p.positive_statement_id).filter(Boolean))];
+    const negIds = [...new Set(pairs.map(p => p.negative_statement_id).filter(Boolean))];
+    const stmtIds = [...new Set([...posIds, ...negIds])];
+
+    const [qRows, stmtRows] = await Promise.all([
+      qIds.length ? query(`SELECT * FROM questions WHERE id = ANY($1)`, [qIds]) : { rows: [] },
+      stmtIds.length ? query(
+        `SELECT s.*,
+          COALESCE(json_agg(DISTINCT spw.word_id) FILTER (WHERE spw.word_id IS NOT NULL), '[]') AS positive_word_ids,
+          COALESCE(json_agg(DISTINCT snw.word_id) FILTER (WHERE snw.word_id IS NOT NULL), '[]') AS negative_word_ids
+         FROM statements s
+         LEFT JOIN statement_positive_words spw ON spw.statement_id = s.id
+         LEFT JOIN statement_negative_words snw ON snw.statement_id = s.id
+         WHERE s.id = ANY($1)
+         GROUP BY s.id`, [stmtIds]
+      ) : { rows: [] },
+    ]);
+
+    const qMap = Object.fromEntries(qRows.rows.map(r => [r.id, r]));
+    const stmtMap = Object.fromEntries(stmtRows.rows.map(r => [r.id, r]));
+
+    const enriched = pairs.map(p => ({
+      ...p,
+      question: p.question_id ? qMap[p.question_id] || null : null,
+      positive_statement: p.positive_statement_id ? stmtMap[p.positive_statement_id] || null : null,
+      negative_statement: p.negative_statement_id ? stmtMap[p.negative_statement_id] || null : null,
+    }));
+
+    res.json(enriched);
+  } catch (err) { next(err); }
+});
+
 // --- Relations ---
 
 // POST   /api/objects/:id/words/:wordId

src/routes/pictures.js

@@ -33,6 +33,31 @@ router.get('/:id', async (req, res, next) => {
   } catch (err) { next(err); }
 });
 
+// GET /api/pictures/:id/words — full word objects linked to this picture
+router.get('/:id/words', async (req, res, next) => {
+  try {
+    const result = await query(
+      `SELECT w.* FROM words w
+       JOIN word_pictures wp ON wp.word_id = w.id
+       WHERE wp.picture_id = $1
+       ORDER BY w.created_at DESC`,
+      [req.params.id]
+    );
+    res.json(result.rows);
+  } catch (err) { next(err); }
+});
+
+// DELETE /api/pictures/:id/words/:wordId
+router.delete('/:id/words/:wordId', async (req, res, next) => {
+  try {
+    await query(
+      `DELETE FROM word_pictures WHERE picture_id = $1 AND word_id = $2`,
+      [req.params.id, req.params.wordId]
+    );
+    res.status(204).end();
+  } catch (err) { next(err); }
+});
+
 // POST /api/pictures — neuen Eintrag anlegen
 router.post('/', async (req, res, next) => {
   try {

src/routes/words.js

@@ -12,10 +12,12 @@ const STATUS_TIMESTAMP = {
 // GET /api/words
 router.get('/', async (req, res, next) => {
   try {
-    const { status, limit = 50, offset = 0 } = req.query;
+    const { status, titel_de, limit = 50, offset = 0 } = req.query;
     const params = [Math.min(parseInt(limit), 500), parseInt(offset)];
-    const where = status ? `WHERE w.status = $3` : '';
+    const conditions = [];
-    if (status) params.push(status);
+    if (status) { conditions.push(`w.status = $${params.length + 1}`); params.push(status); }
+    if (titel_de) { conditions.push(`lower(w.titel_de) = lower($${params.length + 1})`); params.push(titel_de); }
+    const where = conditions.length ? `WHERE ${conditions.join(' AND ')}` : '';
     const result = await query(
       `SELECT w.*,
         COALESCE(json_agg(DISTINCT p.id) FILTER (WHERE p.id IS NOT NULL), '[]') AS picture_ids,