Create the `manyfold` service user before calling `setup_ruby` so `/home/manyfold` exists when rbenv profile snippets are written. Also harden `setup_ruby` by creating `$HOME` if missing, preventing profile-write failures for installers that pass a home directory before creating the user.
Replace `Host $host` with `Host $http_host` so the upstream application receives the original host including the port (e.g. `manyfold:8081`).
Add `X-Forwarded-Host` and `X-Forwarded-Port` headers to ensure the Rails app generates correct absolute URLs instead of defaulting to port 80 when running behind nginx on a non-standard port.
MickLesk