* Defer unique_id assignment during yaml import if dark
* Back out variable name change to simplify.
* Allow config flow yaml setup deferral.
* Fix deferred yaml import
* Code review: only wrap necessary lines in try blk
* Code review: catch possible duplicate unique_id
* Simplify assignment.
* Code review: use timedelta to retry yaml import
* Code review: if a different error occurs, raise it
* Remove current config entry if duplicate unique_id
* Code review: remove unnecessary line.
* Code review: revert change, leave to other PR.
* Code review: remove unnecessary patch & min->sec
* Remove unnecessary else after raise.
* Increase test coverage.
* Check the number of config entries at each stage
* Raise ConfigEntryNotReady when connection fails.
* Log & return false for error on yaml import