Save/Export settings as json

[taos15]

Is your feature request related to a problem? Please describe.
It is vary annoying to have to always set the settings fram start for every filament, or printer. I know the settings can be saved in the browser's local storage, but that is just for one setting.

Describe the solution you'd like
It will be very useful with we have a button, similar to download g-code, so can we can save the current settings (just like it get saved to local storage), and another button to load settings from file.

Additional context
This will allow users to save their setting in a folder like (PLA) with the associated g-code, which will make it easier to retune. It also help with printer with very complicated start and end sequences (mk4s with mmu). We can just upload our config from file. You can think of them as profiles.