Doesn't mind if the expected fields are missing from the config file.

Everything necessary for coordinated concurrency and Github lookups.

Settings read from a config file.

Our global runtime environment.

For Actions that actually had a valid 'latest' release, we store the version thereof.

If changes were detected for a given workflow file, we want to prompt the user for confirmation before applying them.

During the lookup of the latest version of an `Action`, we don't want to call the Github API more than once per Action.