Every deploy stopped at a password prompt. pass-cli is installed, so read
the passwords from the HomeLab vault instead, per command:
switch/boot/test darman@<config> -> nixos-rebuild's sudo prompt
kexec/install root@<host> -> the target's ssh password
nixos-rebuild prompts via getpass(), which reads /dev/tty and ignores a
piped stdin, so that one runs under setsid: no controlling terminal means
getpass falls back to stdin. kexec wraps the master ssh in `sshpass -e`
(scp rides the control socket) and pins password auth so a key can't fall
through into a second prompt; install uses nixos-anywhere's own
--env-password.
Missing pass-cli, a logged-out session, or an absent item all yield an
empty string and the original interactive prompt -- nothing becomes
mandatory. Passwords never reach a command line.
darman
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