- chrono timestamp_opt API: use TimeZone trait method - VfsError::Io/NotFound: use String literals - SendFormat: add PartialEq derive - VfsRaidConfig tests: add disk_paths field - BackupStats test: use relative timestamps - HashSet file tracking: use (String, u64) tuple - BackupStream::receive: clone format before use - collect_file_data: fix temporary lifetime All tests pass: 495 markbase-core + 201 smb-server = 696 total