More reliable vault (.rdm) restore/import for large datasets

CLIENT REQUEST

When restoring a vault backup into a new vault, the operation fails partway through with a client-side TimeoutException (TryGoOfflineException), while the DVLS server shows no particular error in its logs at the same time. A standard "Go offline" works normally under the same conditions.

It would help if bulk import/restore operations (for large numbers of entries) were more robust, for example, with batch processing, automatic retry after a timeout, or a configurable timeout duration rather than failing outright on a large dataset.