feat(README): add link to guidebook docs for usage
We want to make sure that only one place needs to be kept up-to-date w.r.t. using copier and that place is the guidebook. Make sure to link to that location in the README.
GitLab will be updated on 12-Feb-2026 between 12:00 and 14:00. There may be small periods of service instability.
We want to make sure that only one place needs to be kept up-to-date w.r.t. using copier and that place is the guidebook. Make sure to link to that location in the README.