`logicsrc login --device` told users to open
https://logicsrc-credentials-production.up.railway.app/cli/device even when they
had reached the app on the real domain. /cli/device/code built verification_uri
from `config.origin`, which is a single fixed value read from $PUBLIC_ORIGIN, so
the response was wrong for every hostname except the one that variable happened
to name.
Derive the origin from the request instead: whatever host the CLI called is the
host it gets sent back to. Express honours X-Forwarded-Proto/Host here because
server.mjs sets `trust proxy` behind Railway's TLS terminator.
Deliberately scoped to the two device-flow URLs. The WebAuthn expectedOrigin in
passkey.mjs stays pinned to config.origin — validating a signature against a
host the caller supplied would defeat the check.
Note this fixes which URL is *printed*; the host still has to route to this
service for the link to load.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
