Other platforms have webhooks or redirect urls for when a user manually disconnects the app from their (Xero) side.

Currently we will just get an invalid_grant error without knowing if its due to the user disconnecting, or if something has gone wrong and a token refresh failed - requiring the user to reconnect.

This is very useful to determine if the disconnection is intentional, especially when the billing isnt attached to the connection status.

Its also important to know so we can send the correct emails etc