anki: update to 26.05.

[nazaradeh]

Testing the changes

• I tested the changes in this PR: YES

Local build testing

• I built this PR locally for my native architecture, (x86_64-glibc)
• Cross compilation looks iffy. I'm gathering that anki's build process checks the host architecture and will break when cross-compiling. I was able to get it to compile when cross-compiling to aarch64 with a lot of messy lines, checking if we're cross compiling, but I don't know if we'd want that. I don't have an aarch64 machine to test on.
• Build time on my machine is around 6.5 minutes.

Other information

• Added in lame and mpv optional packages as they are small enough and commonly used in Anki. Left out texlive optional package due to a more niche usecase and it significantly increases install size and install time.
• This updates from an older version from 6 years ago. The build system was completely changed since then and is more involved. I modeled this off of the PKGBUILD used in Arch's Anki package: https://gitlab.archlinux.org/archlinux/packaging/packages/anki/-/blob/main/PKGBUILD
• This is my first contribution to void, but I've been a daily user of Anki for many years. I'm happy to keep an eye on this package and update it regularly. Will adopt in the future when I'm allowed to.