fix(assets): strip internal full_count column from list response

The window function COUNT(*) OVER() leaks `full_count` on every row.
Strip it before sending so callers only see actual asset fields.

services/mam-api/src/routes/assets.js

@@ -82,7 +82,7 @@ router.get('/', async (req, res, next) => {
     const total = result.rows.length > 0 ? parseInt(result.rows[0].full_count, 10) : 0;
 
     res.json({
-      assets: result.rows,
+      assets: result.rows.map(({ full_count, ...rest }) => rest),
       total,
     });
   } catch (err) {