This is an amazing script, thank you for providing it!

A few comments:

• It's not clear from the prompt if the composer question is about installing the dependencies of the codebase being changed or dependencies for the script; this could be worded better.
• In terms of workflow, IMHO the dependency question should be first, then questions about the codebase to fix.
• I don't think it's helpful to display the output phpcbf in the terminal, it's an endless firehose. It might be better to turn that output off entirely, or pipe it to a file.

Other than that, I ran it on the Metatag 2.2.x codebase and was impressed with the results. Thank you again!

I think this is brilliant, but for me the real power of OO hooks is being able to replace \Drupal calls with dependency injection. I suspect automating that would be extremely challenging, but I would like to at least see a message at the end saying "Now go convert \Drupal calls to dependency injection." Perhaps, it could provide a list of \Drupal calls to help get started?