Since we start the HomeAssistant shell directly on tty the service
responsible for starting did not restart the shell on exit. Remove the
RemainAfterExit flag to make sure that the shell restarts on exit.
* Start ha-cli on tty1 instead of a getty
Instead of starting a getty start the ha-cli directly. This will show
the banner right on startup with the important information such as IP
address of the instance or the URL to reach it.
* Use default shell as root shell instead of HA CLI
Instead of using the ha-cli.sh script as login shell use the regular
shell. Amongst other things, this allows to run VS Code devcontainers
remotely via SSH or using scp. The HA CLI is still available using the
`ha` command.
