Closes#55.
PR #47 routed ffmpeg-v4l2-request-debian and mpv-fourier-debian to
runs-on: debian-aarch64 (bohr), but their install-deps steps still
called pacman -Syu. That is a latent break that would surface on the
next pkgver bump (currently silent-skipped by check-already-published.sh
since pool versions match the staged PKGVER).
This patch follows PR #50's pattern (daedalus-v4l2{,-dkms}-debian):
- Replace retry pacman -Syu ... with retry apt-get install ...
- Translate Arch package names to Debian (base-devel -> build-essential,
pkgconf -> pkg-config, libdrm -> libdrm-dev, x264 -> libx264-dev, etc.).
- For mpv: drop the "configure [marfrit] repo + pre-install
ffmpeg-v4l2-request-fourier" step entirely. Under apt, stock
libavcodec-dev / libavformat-dev / libavutil-dev provide trixie-ABI
headers matching what mpv-fourier's binary will see at runtime; the
daemon dlopens the fourier libs if installed but doesn't link against
them at build time.
Validated upstream: equivalent debian build-deps installed cleanly in
PRs #44 (libva) and #50 (daedalus).
marfrit