Fix folder display and add validation to file listing operations

- Handle folder names properly in getDisplayName by preserving trailing slash
- Add validation to skip invalid objects during listing
- Add default values for missing object properties (size, lastModified, etag)
- Add debug logging for listObjectsV2 operations to help troubleshoot issues
- Add null checks in deleteFolder to prevent errors with invalid objects

server/api/files/list.ts

@@ -78,6 +78,12 @@ function getFileIcon(filename: string): string {
 }
 
 function getDisplayName(filepath: string): string {
+  // Handle folders (ending with /)
+  if (filepath.endsWith('/')) {
+    const parts = filepath.slice(0, -1).split('/');
+    return parts[parts.length - 1] + '/';
+  }
+  
   // Get just the filename from the full path
   const parts = filepath.split('/');
   const filename = parts[parts.length - 1];