Undo state save and load

[vadosnaprimer]

This option plays a huge role in mistake-proofing, because you can accidentally overwrite a very important savestate, or accidentally load instead of saving, losing lots of your progress.

So whenever a state is about to be saved or loaded, libtas could create a backup savestate with all the current input, and then allow to roll back to it if there was an undesired savestate action. Could even be used to quickly jump between distinct points without keeping them both in actual savestates.

[clementgallet]

It's a good idea, but I'm a little concerned about the extra processing from saving a state each time you would load a state. Some games currently require a significant time to save a state (1 Go+ savestates).

[vadosnaprimer]

Just make it optional. Whoever can afford this could use it.

Another way to simplify this is only storing input data, and not the state itself, also optiuonally.