refactor: QoL changes, bug fixes, prepare for partial rewrite

[revblaze]

TODO

Features

• [ ] Check for Update...
• [ ] User Settings
  • [ ] Enable mod on import
  • [ ] Save/apply changes automatically

Improvements

• [ ] More natural user experience flow
  • [ ] Unsaved changes notifier
• [ ] Database save handling

Fixes

• [ ] Unable to select mod from sidebar in certain cases:
  • [ ] Order reassignments not triggering appropriately
  • [ ] Replace mod with updated version