public/default-textures.json contains block textures from "Pixel Perfection Community Edition" (https://github.com/Athemis/PixelPerfectionCE),
originally created by XSSheep, with updates by StonePendant, freejusticehere, Stingraych, Nova_Wostra and lazerl0rd.
Licence: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/).
Changes: only the textures named in block-names.json were taken, unmodified, and packed into one JSON file (base64 PNGs).
Rebuild with: node tools/make-default-textures.mjs <pack>/assets/minecraft/textures/block