feat: enhance error handling with detailed JSON responses in server API

server-api.js

@@ -48,10 +48,10 @@ app.put('/', (req, res) => {
     fs.writeFile(DATA_FILE_PATH, dataToSave, 'utf8', (err) => {
         if (err) {
             console.error('Error writing data file:', err);
-            return res.status(500).send('Error writing data file');
+            return res.status(500).json({ message: 'Error writing data file', error: err.message || 'Unknown error' });
         }
         console.log(`Data saved successfully to ${DATA_FILE_PATH}`);
-        res.status(200).send('Data saved successfully');
+        res.status(200).json({ message: 'Data saved successfully' });
     });
 });