Move to Pharmaverse

We will be moving this repo from insightengineering to pharmaverse organization.

Possible affected files include:
- README
- DESCRIPTION
- _pkgdown.yml

Inspect README, DESCRIPTION, and _pkgdown.yml for references to the current insightengineering organization and identify the repository metadata or links affected by the move. Confirm that the package documentation and repository references consistently use pharmaverse; the migration is done when no applicable references still point to the old organization.

Written by the indexing model from the issue text.