The `IterationManagerImpl` is aware of the request and storage types to create the iterator. However, it is passing the wrong type to filter and conversion. Retrieving the entries through the `EncoderCache` already converts the values from the storage to the request type. This means anything down the stream receives the elements in the request format.

Since the filter and result transform expect the values to be in the storage format, they end up with values encoded differently or multiple times. We can fix the issue using the request format (if it is not UNKNOWN).

This problem only happens for clients using different media types than the server and iterating with a custom filter.