Add ?search= server-side ILIKE filter to words, pictures, categories

- words: ILIKE across titel_de, titel_en, titel_sv
- pictures: ILIKE on design
- categories: ILIKE across name_de, name_en, name_sv

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

src/routes/words.js

@@ -12,11 +12,16 @@ const STATUS_TIMESTAMP = {
 // GET /api/words
 router.get('/', async (req, res, next) => {
   try {
-    const { status, titel_de, limit = 50, offset = 0 } = req.query;
+    const { status, titel_de, search, limit = 50, offset = 0 } = req.query;
     const params = [Math.min(parseInt(limit), 500), parseInt(offset)];
     const conditions = [];
     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); }
+    if (search) {
+      const p = `%${search.toLowerCase()}%`;
+      conditions.push(`(lower(w.titel_de) LIKE $${params.length + 1} OR lower(w.titel_en) LIKE $${params.length + 1} OR lower(w.titel_sv) LIKE $${params.length + 1})`);
+      params.push(p);
+    }
     const where = conditions.length ? `WHERE ${conditions.join(' AND ')}` : '';
     const result = await query(
       `SELECT w.*,