Multi-File Write Support

Right now GetData saves data to one big file. Support should be added for fetching data from multiple endpoints at once and saving them to separate, smaller files.

**Issue originally raised by Aidan Kovacic.**

Look at the current GetData command's implementation to see how it writes to a single file. Understand the data fetching logic and the file output handling. The change involves modifying the command to handle multiple endpoints and manage concurrent file writes. Check for existing tests related to data fetching and file I/O to understand the expected behavior.

Rédigé par le modèle d'indexation à partir du texte de l'issue.