chore: Rewrite the data layer

[jackh-sh]

While doing maintenance on the code for adding the TouchBar support, I've realised that the data layer could be improved. Currently, everything is stored in a state variable which is very poorly optimised. Also, I cannot read this data from the main process. To combat this, I am going to be rethinking how data moves through the app.

Hopefully, the next version should be easier to maintain and so forth.