Allow setting of credentials for file-based readers/writers

I would also add: introduce the ability to specify user credentials at the time of defining a network connection - similar to how Web Connections are handled.
This would allow authors to access network files using their own credentials or designated credentials, rather than relying solely on the service account. This limitation where only the service account has access to files, is a common constraint encountered with clients. It raises security and governance concerns, as it may unintentionally allow workspace authors to read or write data they shouldn't have access to, simply because the service account does. Even if connections can be shared manually to certain users/groups, enabling per-connection credentials would align with best practices in access control and improve overall security and flexibility.