add logging to ensure file creation logic is working

calendar.test.js

@@ -52,7 +52,7 @@ describe('Calendar Merging API', () => {
 
     test('Merge time-based calendar', async () => {
         const response = await request(server)
-            .post('/merge')
+            .post('/merge') 
             .send({
                 linkGroupName: 'Time Based Calendar',
                 calendars: [

server.js

@@ -54,7 +54,7 @@ app.post('/merge', async (req, res) => {
                     };
                 })
                 .catch((error) => {
-                    console.error(error);
+                    console.error(`Error fetching calendar from ${calendar.url}:`, error);
                     return null;
                 });
         });