Codeberg's HTTP/2 endpoint is flaky and resets connections on
calamares-3.4.2.tar.gz. Forcing --http1.1 with --retry 5 avoids
the 'HTTP/2 stream 7 reset by server' error.
DLAGENTS in PKGBUILD is supported — Arch BBS and makepkg source
confirm it's read from the shell environment after sourcing.