feat: restructure and move apps into their own configs (#2)

home/gui-programs/vscodium.nix

@@ -0,0 +1,13 @@
+{pkgs, ...}: {
+  programs = {
+    # Only for checking markdown previews
+    vscode = {
+      enable = true;
+      package = pkgs.vscodium;
+      extensions = with pkgs.vscode-extensions; [
+        shd101wyy.markdown-preview-enhanced
+        asvetliakov.vscode-neovim
+      ];
+    };
+  };
+}