[FR] Add ability to choose directory to save recording to before recording

[jameshball]

As suggested here with more context and reasoning: https://gearspace.com/board/showthread.php?p=17351970

It might make more sense to just entirely change it so you have to choose a file first because at the moment there's an expensive copying step at the end which is kinda a waste of time.

You could also save the default directory with the project file.