all application options will adapt to environment

when used either with nixos (no home-manager) or home-manager standalone, `features.applications.<name>.enable` options still perform some functionality, rather than assuming a full nixos + home-manager setup like before

modules/features/applications/gui/floorp.nix

@@ -1,10 +1,17 @@
 { inputs, self, ... }: {
   flake.nixosModules.graphics = { pkgs, lib, config, ... }: {
-    home-manager.sharedModules = lib.mkIf (config.features.nixos.stylix.enable) [
-      ({ config, lib, ... }: {
-        stylix.targets.floorp.profileNames = lib.mkIf (config.features.applications.gui.floorp.enable) [ "default" ];
-      })
-    ];
+    options.features.applications.gui.floorp.enable = lib.mkEnableOption "floorp";
+
+    config = let
+      mkIfElse = with lib; p: yes: no: mkMerge [
+        (mkIf p yes)
+        (mkIf (!p) no)
+      ];
+    in lib.mkIf (config.features.applications.gui.floorp.enable) (mkIfElse (config.features.nixos.home-manager.enable) {
+      home-manager.users.grey.features.applications.gui.floorp.enable = lib.mkDefault true;
+    } {
+      environment.systemPackages = [ pkgs.floorp-bin ];
+    });
   };
 
   flake.homeModules.graphics = { pkgs, lib, config, ... }: {