* feat(labrinth): rework v3 side types to a single `environment` field
This field is meant to be able to represent the existing v2 side type
information and beyond, in a way that may also be slightly easier to
comprehend.
* chore(labrinth/migrations): use proper val for `HAVING` clause
* feat(labrinth): add `side_types_migration_review_status` field to projects
