[vega] Update config; make gui config generic. [nvim] Use Snacks smart finder instead of fzf and avoid race condition

system/hosts/vega/default.nix

@@ -4,6 +4,7 @@
     ./configuration.nix
     ./hardware-configuration.nix
     ../../authorized-keys.nix
+    ../../features/gui.nix
   ];
 
   nixpkgs.config.allowUnfree = true;