Fix upload response: ins.rows[0] → ins[0] (rows already destructured)

INSERT RETURNING * was succeeding but response threw TypeError trying to
access .rows[0] on the already-unwrapped rows array. File was saved, DB
record created, but 500 returned. Frontend now gets the record immediately
without needing a refresh.

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

backend/src/index.js

@@ -86,7 +86,7 @@ app.post('/api/attachments/upload/:cash_up_id', { preHandler: [requireAuth, requ
     [cashUpId, fileData.filename, filePath, size, fileData.mimetype, req.user.email, attachmentType, label]
   )
 
-  return ins.rows[0]
+  return ins[0]
 })
 
 app.delete('/api/attachments/:id', { preHandler: [requireAuth, requireCap('count')] }, async (req, reply) => {