fix(backend): close app.post('/api/subdomains') curly braces to fix SyntaxError

backend/server.js

@@ -127,6 +127,8 @@ app.post('/api/subdomains', async (req, res) => {
   } catch (err) {
     res.status(500).json({ error: err.message });
   }
+});
+
 // Excluir Subdomínio (Hostinger + Banco)
 app.delete('/api/subdomains/:id', async (req, res) => {
   if (!HOSTINGER_API_KEY) return res.status(400).json({ error: 'API key não configurada' });