desktop: rename gnome.nix → desktop.nix; switch to nemo

- Rename settings/gnome.nix to settings/desktop.nix (file no longer
  has anything to do with GNOME)
- Replace nautilus with nemo — starts fast, has a hamburger menu,
  no Tracker3/Mutter D-Bus dependencies
- Exclude thunar (pulled in by XFCE) via environment.xfce.excludePackages
- Remove nautilus Tracker dconf workaround (no longer needed)
- Update $mod+E keybind and common.nix import accordingly

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

settings/desktop.nix

@@ -1,4 +1,4 @@
-# settings/gnome.nix — display manager, lightweight fallback session, GTK/Qt theming
+# settings/desktop.nix — display manager, lightweight fallback session, GTK/Qt theming
 { config, pkgs, lib, inputs, ... }:
 {
   config = lib.mkIf (lib.elem config.networking.hostName [ "FredOS-Gaming" "FredOS-Macbook" ]) {
@@ -17,11 +17,14 @@
     # keyring, tracker, or other heavyweight background services.
     services.xserver.desktopManager.xfce.enable = true;
 
+    # Thunar is pulled in by XFCE but we use Nemo instead.
+    environment.xfce.excludePackages = [ pkgs.xfce.thunar ];
+
     # Flatpak for ad-hoc app installs via Bazaar
     services.flatpak.enable = true;
 
     environment.systemPackages = with pkgs; [
-      nautilus             # file manager — works standalone without a GNOME DE
+      nemo                 # file manager
       adwaita-icon-theme
       gnome-themes-extra
       adwaita-icon-theme-legacy
@@ -48,10 +51,6 @@
       # Minimal titlebars — stylix manages the GTK theme; we layer our
       # headerbar shrink on top via stylix.targets.gtk.extraCss.
       gtk.enable = true;
-      # Disable Tracker search — Nautilus tries to connect to the Tracker3
-      # D-Bus service at startup for recursive search. Outside GNOME the
-      # service isn't running, causing a multi-second D-Bus timeout on launch.
-      dconf.settings."org/gnome/nautilus/preferences".recursive-search = "never";
 
       stylix.targets.gtk.extraCss = ''
         headerbar { min-height: 0; padding: 0; margin: 0; }

settings/hyprland.nix

@@ -218,7 +218,7 @@ in
           # Mirror the GNOME bindings so muscle memory carries over
           bind = [
             "$mod, T, exec, $term"
-            "$mod, E, exec, nautilus"
+            "$mod, E, exec, nemo"
             "$mod, R, exec, $menu"
             "$mod, Q, killactive"
             "$mod SHIFT, E, exit"