switch nixfmt to alejandra to format nix code

pkgs/helix/default.nix

@@ -4,13 +4,11 @@
   inputs,
   callPackage,
   ...
-}:
-let
+}: let
   inherit (inputs.helix.packages."${pkgs.system}") helix;
-  runtime = callPackage ./runtime.nix { };
+  runtime = callPackage ./runtime.nix {};
   runtimeInputs = (
-    with pkgs;
-    [
+    with pkgs; [
       idris2Packages.idris2Lsp
       lua-language-server
       bash-language-server
@@ -30,7 +28,7 @@ let
       marksman
       nixd
       deno
-      nixfmt-rfc-style
+      alejandra
       vscode-langservers-extracted
       fish-lsp
       gopls
@@ -45,16 +43,16 @@ let
     ]
   );
 in
-pkgs.symlinkJoin {
-  name = "helix-wrapped";
-  paths = [ helix ];
-  inherit (helix) meta;
-  buildInputs = [
-    pkgs.makeWrapper
-  ];
-  postBuild = ''
-    wrapProgram $out/bin/hx \
-    --suffix PATH : ${lib.makeBinPath runtimeInputs} \
-    --set HELIX_RUNTIME ${runtime}
-  '';
-}
+  pkgs.symlinkJoin {
+    name = "helix-wrapped";
+    paths = [helix];
+    inherit (helix) meta;
+    buildInputs = [
+      pkgs.makeWrapper
+    ];
+    postBuild = ''
+      wrapProgram $out/bin/hx \
+      --suffix PATH : ${lib.makeBinPath runtimeInputs} \
+      --set HELIX_RUNTIME ${runtime}
+    '';
+  }

pkgs/helix/runtime.nix

@@ -4,10 +4,8 @@
   stdenv,
   runCommandNoCCLocal,
   ...
-}:
-let
-  buildGrammar =
-    grammar:
+}: let
+  buildGrammar = grammar:
     stdenv.mkDerivation {
       pname = "helix-tree-sitter-${grammar.name}";
       version = grammar.version;
@@ -81,20 +79,20 @@ let
       }
     )
     |> lib.mapAttrsToList (_: value: "ln -s ${value.value}/${value.name}.so $out/${value.name}.so");
-  grammarDir = runCommandNoCCLocal "helix-grammars" { } ''
+  grammarDir = runCommandNoCCLocal "helix-grammars" {} ''
     mkdir -p $out
 
     ${builtins.concatStringsSep "\n" grammarLinks}
   '';
-  queryDir = runCommandNoCCLocal "helix-query" { } ''
+  queryDir = runCommandNoCCLocal "helix-query" {} ''
     mkdir -p $out
 
     ${builtins.concatStringsSep "\n" queries}
   '';
 in
-runCommandNoCCLocal "helix-runtime" { } ''
-  mkdir -p $out
+  runCommandNoCCLocal "helix-runtime" {} ''
+    mkdir -p $out
 
-  ln -s ${grammarDir} $out/grammars
-  ln -s ${queryDir} $out/queries
-''
+    ln -s ${grammarDir} $out/grammars
+    ln -s ${queryDir} $out/queries
+  ''