OptionalprThe PR behind reason, for the PR reasons.
Strongest reason when several apply (open PR, then claim, closed PR, merged PR).
OptionalsinceISO time of the user's latest engagement step: the claim stamp, or when the PR was opened. Comments at or before it were answered by the engagement itself, so only later ones can be replies to the user. Absent when the PR's opening time is not known (older ledger entries); the user's last comment is the baseline then.
Why a commented-issue entry was scanned under the engaged rule (#1862).