Multi-lists for Muzei

Oct 3, 2022

- The app now supports Muzei 3.4's custom action icon.
Muzei 3.x are still supported, though it is highly recommended to upgrade the Muzei altogether if at all possible.

- Incompatibility: the app no longer supports Muzei 2.x running on Android 4.4 and beyond.

- Bug fixes, incl.:
- infinite crash loop if cache files were cleared.
- fix sort on Android 10

- Subtle performance tunings.

Bugs not fixed yet:
- There have been crashes on OnePlus One A0001. I'll continue investigating it.