Is there a way to save out the charge history data, either from the car or Toyota app, as a document file? pdf, csv, xml...
No, not from Toyota. You only have the Charge History and Charge Detail screens to go back and look at for that. And even at that the kWh Toyota reports is not accurate but just some estimate they make up. For real data you'd have to use some third party EVSE that gathers that data as it delivers power to the charger.