An RFC-3339 instant the CLI wrote, as the reader’s own wall clock:
HH:MM:SS for today’s, the date too for anything older, because a turn
read from a transcript can be weeks old and a bare time would read as
today. None for a string that does not parse, so a malformed row draws
no clock rather than a fabricated one.
The OS-configured IANA timezone, read dynamically. Uses
iana-time-zone (multithread-safe on Unix, unlike
time::UtcOffset::current_local_offset, which errors in a threaded
process). Falls back to UTC with a warn only when the zone can’t be
resolved - the rare exception, so “today” tracks the user’s wall clock.