## About the changes
https://linear.app/unleash/issue/2-425/variants-crud-new-environment-cards-with-tables-inside-add-edit-and
Basically created parallel components for the **variants per
environments** feature, so both flows should work correctly depending on
the feature flag state. Some of the duplication means that cleanup
should be straightforward - Once we're happy with this feature it should
be enough to delete
`frontend/src/component/feature/FeatureView/FeatureVariants/FeatureVariantsList`
and do some little extra cleanup.
I noticed we had some legacy-looking code in variants, so this involved
*some* rewriting of the current variants logic. Hopefully this new code
looks nicer, more maintainable, and more importantly **doesn't break
anything**.
Relates to [roadmap](https://github.com/orgs/Unleash/projects/10) item:
#2254
### Important files
Everything inside the
`frontend/src/component/feature/FeatureView/FeatureVariants/FeatureEnvironmentVariants`
folder.
