Preferences only save when quitting the program

[Bentroen]

Preferences and anything that's stored in the settings file (i.e. schematic/data pack export settings, dialogs, recent songs) are only saved to the file when you quit the program normally (i.e from File > Exit or by clicking the Close button and confirming). If you leave the program open for days and then it crashes/your computer restarts, none of the stuff you changed during that time will appear the next time you open.

Fix: save preferences whenever the recent song file is updated, a data pack/schematic is exported, and the Preferences window is closed.