- Add specialArgs to nix-deck (was missing nixpkgs-unstable, causing
infinite recursion when roles/local-inference evaluated it)
- Move local-inference import out of roles/default.nix: its module-level
disabledModules/imports conflict with nix-deck's unstable-based nixpkgs
- Import local-inference directly in zix790prors (the only machine that
enables it)
- Add custom-qmd and custom-opencode to CI build-and-cache packages