Run fn under policy (none = one attempt, still recorded) and resolve with its answer, or reject with the LAST
attempt's own error. fn gets the attempt's AttemptContext: pass signal to the work, read timeLeftMs(),
and report an SDK's own retries with observed().
Run
fnunderpolicy(none = one attempt, still recorded) and resolve with its answer, or reject with the LAST attempt's own error.fngets the attempt'sAttemptContext: passsignalto the work, readtimeLeftMs(), and report an SDK's own retries withobserved().