docs: add some todos describing program replacements

modules/nixos/bundles/desktop.nix

@@ -19,10 +19,12 @@ in
     environment.systemPackages = with pkgs; [
       # keep-sorted start
       beeper
+      # TODO: replace with lue/epy
       calibre
       cameractrls-gtk3
       # https://github.com/NixOS/nixpkgs/issues/437865
       # jellyfin-media-player
+      # TODO: replace with sc-im/visidata
       onlyoffice-desktopeditors
       sleek-todo
       textsnatcher

modules/nixos/features/plasma.nix

@@ -23,6 +23,7 @@ in
         # keep-sorted start
         kget
         kontact
+        # TODO: replace with transmission
         ktorrent
         kzones
         # keep-sorted end