fix: Use integer for userId in JWT

[DafyddLlyr]

Regression tests running here - https://github.com/theopensystemslab/planx-new/actions/runs/11600394961

[github-actions]

Removed vultr server and associated DNS entries

[DafyddLlyr]

This isn't the right way forward here, according to the docs -

Session variables are currently expected to only be strings and should be encoded based on Postgres's literals for the relevant type.

Source: https://hasura.io/docs/2.0/auth/authorization/roles-variables/

Hasura should be casting this correctly, the insert error I'm getting when trying to use the demoUser role must be coming from somewhere else. Looking into it atm!