Restructure into a multi-machine flake and add the enzo laptop

Split the single-host config into a shared minimal base plus opt-in
profiles, and add a second machine (enzo laptop) alongside kusanagi.

- flake: add mkMachine helper; declare nixosConfigurations.kusanagi and
  .enzo; add the disko input; move overlays per-machine.
- common/: minimal base only (boot, networking, tailscale, locale, nix
  settings, neovim editor). Old configuration.nix/programs.nix removed.
- profiles/: coarse opt-in bundles (desktop, dev, apps). kusanagi imports
  all three and stays byte-for-byte identical to the running system.
- machines/kusanagi/: all workstation-only config (ROCm, Scarlett audio,
  optical-disc archiving, NAS mounts, kavita/immich/ollama); hardware
  config moved here unchanged. User stays 'henz'.
- machines/enzo/: new laptop. Declarative LUKS+btrfs via disko
  (LVM-on-LUKS, TPM2+PIN unlock, zram + encrypted swap for
  suspend-then-hibernate); its own minimal niri desktop with
  playback-only audio (no rtkit/jack); user 'hwebs'.

Assisted-by: Claude:claude-opus-4-8

1 files changed, 30 insertions, 0 deletions

diff --git a/profiles/apps.nix b/profiles/apps.nix
new file mode 100644
index 0000000..279ef03
--- /dev/null
+++ b/profiles/apps.nix
@@ -0,0 +1,30 @@
+# Apps profile: GUI and personal applications, plus gaming. Opt-in per machine.
+{ pkgs, ... }:
+
+{
+  programs.steam.enable = true;
+  programs.firefox.enable = true;
+
+  environment.systemPackages = with pkgs; [
+    itch
+  ];
+
+  users.users.henz.packages = with pkgs; [
+    discord
+    vlc
+    gimp
+    inkscape
+    darktable
+    protonmail-desktop
+
+    # media tooling
+    imagemagick
+    ffmpeg
+
+    flatpak
+
+    # TUI apps
+    newsboat
+    castero
+  ];
+}