The SSH_TTY guard was too broad — it broke local terminal sessions on
macOS. Use platform-specific conditions: Darwin omits the SSH_TTY check
(always exec nu unless IDE/skip), Linux keeps it (only exec nu for
interactive SSH, leaving non-interactive sessions like Codex in zsh).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Set thegeneralist-central's user shell to zsh (matching macOS pattern).
Drop the isDarwin guard on .zshrc generation so all hosts get the
SSH_TTY-gated nu exec — non-interactive SSH (Codex etc.) stays in zsh,
real interactive sessions still land in nu.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>