Animated avif image viewers

[avidseeker]

Somewhat related to: #2634 and #2640

Is there an image viewer supporting animated avifs?

• nsxiv based on imlib2 based on libheif doesn't support this: https://codeberg.org/nsxiv/nsxiv/issues/529
• feh is also based on imlib2
• mpv based on ffmpeg doesn't support decoding animated avif
• pqiv: Animated avif support phillipberndt/pqiv#253