Add healthcheck

[alex4108]

Is your feature request related to a problem? Please describe.
Adding some kind of command line or network health check to the container so that orchestration services can detect when the container is unhealthy.

Describe the solution you'd like
Include a shell script to check status of the container, eg a new script in scripts/healthcheck.sh like:

output=$(ps aux | grep palworld)
if [[ /* output says palworld is running */]]; then
  exit 0
fi

exit 1

Describe alternatives you've considered
none!

Additional context