debian/rules: Source cargo env before calling cargo
- Add `. "$HOME/.cargo/env"` to override_dh_auto_build
build-alpine.sh: Use /home/builduser for all paths
- PKGDIR=/home/builduser/apk-package (accessible by builduser)
- WORKSPACE_DIR=/home/builduser (for APKBUILD package function)
- Removed duplicate else line
build-arch.sh: Copy repo to accessible directory
- Copy repo contents to /home/builduser/repo before makepkg
- Run makepkg in /home/builduser/repo (not act cache path)