test: VM smoke and Lightning regtest suites

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/refactor-smoke.nix

@@ -0,0 +1,80 @@
+# refactor-smoke — headless VM boot test for autonomous refactor runs
+#
+# The "closed environment" for aggressive refactors is the *worktree* at
+# ~/nixos-refactor/ plus the lack of sudo (so `omni-rebuild switch`
+# can't activate on bohm). This test gives Claude an objective
+# success/fail signal it can iterate against without a human in the loop.
+#
+# Run from a worktree of /etc/nixos:
+#   nix build .#checks.x86_64-linux.refactor-smoke -L
+#
+# Or as part of the full check suite:
+#   nix flake check --keep-going -L
+#
+# Extension points (the starter is intentionally minimal):
+#   - Add `imports` to `nodes.machine` as you bring more modules under
+#     test. Mind: graphical bits (Hyprland, greetd) are skipped — they
+#     need a real display and aren't easy to assert against in QEMU.
+#   - Add assertions to `testScript` as you pin more behavior. Useful
+#     idioms:
+#       machine.succeed("systemctl is-active <unit>.service")
+#       machine.succeed("test -f /etc/<path>")
+#       machine.succeed("grep -q '<line>' /etc/<file>")
+{
+  nixpkgs,
+  system ? "x86_64-linux",
+  ...
+}:
+
+let
+  pkgs = import nixpkgs {
+    inherit system;
+    config.allowUnfree = true;
+  };
+in
+pkgs.testers.runNixOSTest {
+  name = "omni-refactor-smoke";
+
+  nodes.machine =
+    {
+      config,
+      pkgs,
+      lib,
+      ...
+    }:
+    {
+      # Match the real machine's primary user so home-managed paths
+      # resolve identically when the test grows to exercise them.
+      users.users.padreug = {
+        isNormalUser = true;
+        uid = 1000;
+        extraGroups = [ "wheel" ];
+      };
+
+      # Tools the refactor surface should always ship. Mirror this list
+      # to whatever your CLAUDE.md / dev-env claims is installed.
+      environment.systemPackages = with pkgs; [
+        git
+        pnpm
+        neovim
+      ];
+
+      system.stateVersion = "24.11";
+    };
+
+  testScript = ''
+    machine.start()
+    machine.wait_for_unit("multi-user.target")
+
+    # Boot reached multi-user.
+    machine.succeed("uptime")
+
+    # Primary user exists with expected uid.
+    machine.succeed("test $(id -u padreug) -eq 1000")
+
+    # Key tools functional, not just present on PATH.
+    machine.succeed("git --version")
+    machine.succeed("pnpm --version")
+    machine.succeed("nvim --version | head -1")
+  '';
+}