The retest-comment workflow fired on 'reopened' as well as 'opened', and
canPostRetestComment gated on the issue author's association, not the
reopen actor's. Since non-collaborator reporters cannot reopen
maintainer-closed issues, a reopened event is in practice always a
deliberate maintainer decision, and the bot would post version-retest
boilerplate that contradicts the maintainer's own comment while planting
the needs-retest auto-close marker on an issue they chose to keep open
(seen on #1471).
Restrict the trigger and the guard to 'opened' and pin the reopened skip
with a test.
Separate silent issue metadata sync from public retest guidance so maintainer edits and reporter-facing comments do not share the same workflow boundary. Extract the shared parsing and classification logic into a local helper with a small node test so both workflows stay in sync without duplicating the script.
