refactor(keyboard): nixify 'vortex-core' directory

home/modules/keyboard/default.nix

@@ -0,0 +1,16 @@
+{
+  config,
+  lib,
+  ...
+}:
+
+{
+  options.keyboard.vortexCore.enable = lib.mkEnableOption "Vortex Core keyboard configuration files";
+
+  config = lib.mkIf config.keyboard.vortexCore.enable {
+    home.file.".vortex-core" = {
+      source = ./vortex-core;
+      recursive = true;
+    };
+  };
+}