- chunk download doesn't loop on permanent errors
- decryption errors are considered permanent - local worker doesn't retry
- update replica retries; to do - consider use for this field, or remove it
- rcv file Error status - to prevent repeat reads of chunks for download, files for decryption; also plan to use it for filtering on cleanup
- error string saved in separate field for debugging (not part of status type)
- agent event for rcv file errors
