build(flake/nix): adding the default compilation env var

flake.nix

@@ -35,7 +35,7 @@
       in
       {
         devShells.default = pkgs.mkShell {
-          name = "irc-42";
+          name = "libasm-42";
           buildInputs =
             with pkgs;
             [
@@ -61,6 +61,8 @@
             );
 
           shellHook = ''
+              export AS=nasm
+              export CC='clang'
               printf "\n\033[0;90mASM env loaded for: \033[38;5;220m${system}\033[0m\n"
             '';
         };