Ability to change screen selection *after* Wayland sharing token storage

Currently after the user makes a sharing selection the Wayland token is stored to allow them to make a faster selection / recording on the next run. However this then also prevents them from changing their selection until token expiry which is unhelpful.

When running Wayland there needs to be an option to clear the token / display the current sharing selection / make a new sharing selection (or perhaps all three!).