added nvchad from nvchad4nix

flake.nix

@@ -17,6 +17,11 @@
       url = "github:0xc000022070/zen-browser-flake";
       #inputs.nixpkgs.follows
     };
+
+    nix4nvchad = {
+      url = "github:nix-community/nix4nvchad";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
   };
 
   outputs =