Running `pnpm --filter @parking/server seed-admin` with no env vars now prompts
for a username (blank -> "admin") and then a password. Env vars (ADMIN_USER /
ADMIN_PASS) and a CLI arg still work for non-interactive installs.
Read prompts through a single readline async line-iterator so it's robust over
both a TTY and a pipe (chaining readline/promises question() over a pipe could
drop buffered lines). Verified: default + custom username, env-var path.
julian
0a8258a672