**BREAKING CHANGE**: DEFAULT_ENV changed from `default` (should not be
used anymore) to `development`
## About the changes
- Only delete default env if the install is fresh new.
- Consider development the new default. The main consequence of this
change is that the default is no longer considered `type=production`
environment but also for frontend tokens due to this assumption:
724c4b78a2/src/lib/schema/api-token-schema.test.ts (L54-L59)
(I believe this is mostly due to the [support for admin
tokens](https://github.com/Unleash/unleash/pull/10080#discussion_r2126871567))
- `feature_toggle_update_total` metric reports `n/a` in environment and
environment type as it's not environment specific
We're migrating to ESM, which will allow us to import the latest
versions of our dependencies.
Co-Authored-By: Christopher Kolstad <chriswk@getunleash.io>
