pub(crate) fn ceil_to_whole_sec(now: DateTime<Utc>) -> Result<i64>Expand description
Rounds a Utc instant up to the next whole second (Unix seconds), with
nanosecond precision.
timestamp() / timestamp_millis() floor the sub-second fraction; using
them unchanged could produce a start_secs in the past relative to the
exact prepare instant, which would make the very first evaluation due before
the flow finished being prepared. Uses checked arithmetic so an instant at
the very end of the i64 second range yields an explicit error instead of
wrapping.