fontconfig: keep binaries; add script to tools for additional fonts

[xzn]

Summary

Add fc-cache and friends binaries (they are less than half a megabyte total before compression) to allow updating fontconfig cache. (This is the main change)

Add a script to install Noto CJK fonts, with placeholder image. (As an example but it's useful anyhow)

Testing

Fresh clean build on Ayn Thor. Newly installed fonts works in Steam and Heroic file browser. Should work anywhere where fontconfig is used.

Additional Context

Should supersede #2875

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AI Usage

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Did you use AI tools to help write this code? NO

[ddordie]

Tested on-device: Serif CJK overrides the system sans-serif UI font, breaking Chinese display. Maybe switch to Sans2.004?

[xzn]

Tested on-device: Serif CJK overrides the system sans-serif UI font, breaking Chinese display. Maybe switch to Sans2.004?

Good point! Added Sans and Mono fonts; also added fontconfig config file.

Still not working in retroarch though hmmm, maybe will need to adjust font manually there.

[loki666]

in which scenario is this usefull ?

[xzn]

I haven't needed this personally, but there are games on Steam (say Touhou fangames) that has Chinese descriptions, which do not get displayed in the Steam store web browser due to lack of fonts. Likely the same for Heroic.

For Retroarch the script now downloads Noto Sans CJK ttf fonts to /storage/assets/fonts. After that if the user manually sets the desired font in retroarch settings, the language can then be set to one of the CJK languages and have the UI display correctly (instead of having boxes).

fc-cache is likely useful for other fonts in addition to Noto CJK, in case user wants to install their own fonts manually, so they can update fontconfig cache.

Not sure about EmulationStation though? It seems to have its own CJK fonts.

[r3claimer]

I dont really love the idea of adding a install script to to the tools section to just install a font set.

[xzn]

Agree on that, I think at the minimum though the fc-cache binary should be kept. (Currently without this pr all fontconfig binaries are removed from install).

That way user can install their own font and update fontconfig cache. I can update the pr to do just that part. If you have idea on where to put the font install script let me know and I can update it as well. One way would be to just have the fc-cache and friends binaries, and have some doc on wiki somewhere on how to add custom fonts.

[spycat88]

I dont really love the idea of adding a install script to to the tools section to just install a font set.

I think this is preferred for me, it's an additional 13MB on the images installing CJK font permanently. Thoughts?