Shell: Changed default shell from ion to zsh for all user accounts
in base.toml, redbear-mini.toml, redbear-full.toml, and greeter config.
zsh 5.9 is already ported and builds (ZSH-PORTING-PLAN — fully implemented).
ion is kept as fallback/alternative.
Cookbook: pkgar staging fallback — when a dependency's target pkgar
doesn't exist, fall back to repo/<target>/<pkg>.pkgar. This fixes the
kf6-kitemviews build failure where libwayland's pkgar was missing from
the target directory.
vasilito
5862255060