nixos/orca: init, enable by default on Plasma (#339069)

nixos/modules/module-list.nix

···
   ./security/systemd-confinement.nix
   ./security/tpm2.nix
   ./security/wrappers/default.nix
+  ./services/accessibility/orca.nix
   ./services/accessibility/speechd.nix
   ./services/admin/docuum.nix
   ./services/admin/meshcentral.nix

nixos/modules/services/accessibility/orca.nix

···
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+let
+  cfg = config.services.orca;
+  inherit (lib)
+    mkEnableOption
+    mkIf
+    mkPackageOption
+    ;
+in
+{
+  options.services.orca = {
+    enable = mkEnableOption "Orca screen reader";
+    package = mkPackageOption pkgs "orca" { };
+  };
+
+  config = mkIf cfg.enable {
+    environment.systemPackages = [ cfg.package ];
+    services.speechd.enable = true;
+  };
+}

nixos/modules/services/desktop-managers/plasma6.nix

···
     xdg.portal.configPackages = mkDefault [kdePackages.xdg-desktop-portal-kde];
     services.pipewire.enable = mkDefault true;
 
+    # Enable screen reader by default
+    services.orca.enable = mkDefault true;
+
     services.displayManager = {
       sessionPackages = [kdePackages.plasma-workspace];
       defaultSession = mkDefault "plasma";

nixos/modules/services/x11/desktop-managers/cinnamon.nix

···
       ] ++ utils.removePackagesByName [
         # accessibility
         onboard
-        orca
 
         # theme
         sound-theme-freedesktop
···
           buildPortalsInGnome = false;
         })
       ];
+
+      services.orca.enable = mkDefault (notExcluded pkgs.orca);
 
       xdg.portal.configPackages = mkDefault [ pkgs.cinnamon-common ];
 

nixos/modules/services/x11/desktop-managers/gnome.nix

···
         isSystem = true;
       };
 
+      services.orca.enable = notExcluded pkgs.orca;
+
       fonts.packages = with pkgs; [
         cantarell-fonts
         dejavu_fonts
···
             pkgs.gnome-shell-extensions
             pkgs.gnome-tour # GNOME Shell detects the .desktop file on first log-in.
             pkgs.gnome-user-docs
-            pkgs.orca
             pkgs.glib # for gsettings program
             pkgs.gnome-menus
             pkgs.gtk3.out # for gtk-launch program

nixos/modules/services/x11/desktop-managers/pantheon.nix

···
         # https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1443
         pkgs.pantheon.mutter
       ];
+      services.orca.enable = mkDefault (notExcluded pkgs.orca);
       systemd.packages = with pkgs; [
         gnome-session
         pantheon.gala
···
         adwaita-icon-theme
         gtk3.out # for gtk-launch program
         onboard
-        orca # elementary/greeter#668
         sound-theme-freedesktop
         xdg-user-dirs # Update user dirs as described in https://freedesktop.org/wiki/Software/xdg-user-dirs/
       ]) ++ (with pkgs.pantheon; [

nixos/modules/services/x11/desktop-managers/plasma5.nix

···
         pkgs.media-player-info
       ];
 
+      # Enable screen reader by default
+      services.orca.enable = mkDefault true;
+
       services.displayManager.sddm = {
         theme = mkDefault "breeze";
       };