As Vaultwarden is meant to replicate the upstream project as much as possible the devs tends to try to avoid changes on how things are implemented.
I would recommend going to the official forums for further support with this.
There does appear to be a similar posting I found so you may have luck with the suggested OAUTH toolkit program recommended there.
Edit: I found supported features within the official version for API support within the CLI to authenticate.
https://bitwarden.com/help/article/personal-api-key/
But this appears not to be in Vaultwarden yet, hopefully it does get implemented to fullfil this request.