Add the requirePcscd option to the nix-darwin module for consistency
with NixOS and home-manager modules. On macOS, CryptoTokenKit typically
handles YubiKey communication automatically, but this option is provided
for API consistency.
Add sops.gnupg.package option to NixOS, home-manager, and nix-darwin
modules, allowing users to specify a custom gnupg package instead of
the default pkgs.gnupg.
This enables use of bleeding-edge GPG versions with post-quantum
encryption algorithms like Kyber, addressing "store now, decrypt
later" threat models.
