Set the package's "MediaWords::Controller::Api::V2::ExtractLines" name at the top of the file too
Remove authentication / throttling / logging action roles for controller's actions "single" and "list" because they don't exist in ExtractLines controller; add appropriate action roles ("authenticated with public API key; requests are throttled (limited); requests are logged") to the single "storyLines" action role
Rename "storyLines" controller action to "story_lines" because the rest of the code uses underscores instead of camelCase (e.g. stories/put_tags, media_sets/list, stories_public/single, etc.)