Rename azos-core station suite to desktop; move discord out to azos/features

Mirrors the azos-core change: station is renamed desktop (its apps are
generically useful on any machine, work included), discord moves to its
own standalone azos/features/discord (personal-only, so it lives in the
azos project rather than azos-core), and azos-emacs-station becomes
azos-emacs-desktop in lauretta's emacs config to match.

features/lauretta/emacs/_pkg.nix

@@ -12,7 +12,7 @@ orgTrivialBuild {
     pkgs.azos-emacs-dev
     pkgs.azos-emacs-editor
     pkgs.azos-emacs-exwm
-    pkgs.azos-emacs-station
+    pkgs.azos-emacs-desktop
 
     agent-shell
     elfeed-protocol