user.nix fetches SSH keys via fetchurl+readFile (import-from-derivation);
--no-build blocks the IFD fetch, failing eval in a fresh store. Evaluating
the toplevel/activation drvPaths permits IFD without building the toplevels.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Job-level continue-on-error still rendered red and skipped statix/deadnix
after nixfmt failed. Step-level lets all three run without failing the job.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>