Mon KITAS ou KITAP de retraite expire-t-il lorsque je quitte le pays ?

No. The KITAS de retraite et KITAP retraite are multiple-entry permits, meaning you can enter and leave Indonesia as often as you want during the validity period.

Your KITAS/KITAP will pas expire automatically just because you travel abroad.
It only expires on its official end date, unless cancelled intentionally (e.g., through an OEB).