publish ffprobe-static as @derhuerst/ffprobe-static

use 6.1.1 binaries, skip FreeBSD x64 & win32-ia32 binaries 💥💚; 5.3.0

CI: fix binary publishing by giving write permissions 💚

add pretest script to download binaries before running test

minor-upgrade deps & dev deps

readme: document build requirements, minor tweak 📝

readme: explain local dev setup procedure 📝

CI: adapt to workspace repo structure 💚

CI test workflow: run npm install --workspaces 💚

upgrade deps & dev deps

package-lock.json: use tabs for indentation

upgrade deps & dev deps

use 6.0 binaries; 5.2.0

package-lock.json: add packages/*

CI: fix binaries publishing 💚