Check quota before upload

[claucambra]

Nextcloud offers a feature for server admins which allows them to limit the maximum storage use of a given user or groups of users by applying a quota. If uploading a file will result in the user exceeding their set storage quota, the server returns an error to the desktop client.

The macOS virtual files client does not yet correctly handle the storage quota limit. Your task is to implement support for this feature, leveraging the available features in the File Provider API to do so in a way that will allow the system and the user to decide the best course of action upon encountering this error.