I'm completely noob here, but I've looked at the development manual and I see the Track object. The only metadata listed is 'Name'. Clearly there's more somewhere (duration, etc), but where is this stored? I'm specifically interested if there's a location for lyrics, and if so if there are any plugins to auto-fill those lyrics?
There is no lyrics meta information recorded. Duration, what track number, and duration are available. A media item and part contain additional information about the actual track itself.