Support terraform config for auto-detect

It would be great if tfenv could also directly support .tf to automatically detect which version to use - instead of having to manually run tfenv install min-required.

This would make it possible to avoid having to manage the version in two different files.

An enhancement to support this could resolve #230

Is there any chance to have this implemented?

@IMKnysh For this reason I moved to tfswitch which seems to be more robust.

btw. you can also use tenv that support Terraform as well as OpenTofu (and Terragrunt :) ) in one tool. It allow you to simplify version management and can do much more, than tfswitch.