pyracerz: Games crashes with Permission denied when writing highscores

Hi,

When someone absolutely has to write a setgid C helper for a Python
program that can be done, I did it back then and could recycle it.
  https://sources.debian.org/src/systemd-cron/2.7.0-2/src/bin/crontab_setgid.c

But still it goes against the recent discussion about Games Team policies
and I would here rather drop the /var/games patches altogether.
   https://lists.debian.org/debian-devel-games/2025/12/msg00016.html

As a transition measure, at first start the game would try to copy
an existing score file from /var/games ;
postrm would purge /var/games/pyracerz/pyracerz.conf as usual

~ ~ ~

I could maybe use dh-cruft for that purpose, the generated
/var/lib/dpkg/info/pyracerz.postrm would look similar
and that's not the main point discussed here.
... but help in dh-cruft on how to translate the
"rmdir --ignore-fail-on-non-empty /var/games"
in some declarative stanza is welcome

...or maybe even generating d/postrm from debian/<game>.tmpfiles ... :-)
https://salsa.debian.org/games-team/iortcw/-/commit/aa9bd17b85ac4756bfc4d3b10131d44891fa7ec0
-> nice work


Greetings

Alexandre