chore: advance workstation workflow pilots

modules/capabilities/skills/nixos-maintainer/SKILL.md

@@ -0,0 +1,29 @@
+---
+name: nixos-maintainer
+description: Maintain this NixOS and Home Manager flake by inspecting, changing, simplifying, or validating its configuration. Use for system configuration work in the NixOS repository, not generic Nix questions or unrelated projects.
+---
+
+# NixOS Maintainer
+
+Read the applicable `AGENTS.md` and the complete current owner of the behavior
+before editing. Trace its imports through the host, profile, and capability
+modules so the change lands at the narrowest shared level that matches its real
+scope.
+
+Prefer an existing module or native NixOS/Home Manager option. Keep mutable,
+secret, credential, and application-owned state outside the Nix store. Verify
+unfamiliar pinned interfaces against the exact package source or current primary
+documentation.
+
+Preserve unrelated work in a dirty tree. Make the smallest complete change,
+format touched Nix files with the repository formatter, and validate only the
+affected hosts. Ordinarily run:
+
+```sh
+nix flake check --no-build --quiet
+nix build --no-link --quiet .#nixosConfigurations.<host>.config.system.build.toplevel
+```
+
+Start with a narrower evaluation when it can fail faster. Inspect targeted
+failure logs only. Do not switch or boot a generation unless the user explicitly
+requests activation.