[Windows] Ability to activate multiple modes simultaneously

First of all, thank you for developing this app for Windows!

This is just a nit-picky QoL suggestion (since I think that the app is already quite well-made at this point), but I thought it might be nice to allow users to activate multiple modes at once (e.g. grammar correction + email).

In case an instruction within an active mode conflicts with another active mode’s, we could also consider an option to set priorities, if the multi-mode function were to be integrated.