Reverse-engineer changes in a workflow

[ForNeVeR]

Generaptor should be able to reverse-engineer changes in a workflow file: having the set of action versions in the actual file, it should be able to update its script.

This is targeting the cases when tools such as Dependabot update the target workflow files, and they don't know about the script that generated it.

To do this, we'll need to create a convention of allowing overriding any action versions via the generator functions, and keeping some kind of metadata for each item, to figure out what source element / function call generated it. And then use some parser / Myriad to apply the changes back to the source.