Note this does not look like a segfault to me:
LoadError: /var/www/discourse/vendor/bundle/ruby/3.3.0/extensions/aarch64-linux/3.3.0/mini_racer-0.17.0.pre12/mini_racer_extension.so: undefined symbol: __libc_single_threaded (LoadError)
Likely this is caused cause the actual running container is somehow running glibc < 2.32.
The fix here should be:
./launcher rebuild app
via host.