maint: Run nix stuff through the formatter

There are several choices for formatting Nix code, but IMHO alejandra is the
right kind of opinionated: <https://github.com/kamadorueda/alejandra>.

default.nix

@@ -8,4 +8,5 @@ in
       }
     ) {
       src = ./.;
-}).defaultNix
+    })
+  .defaultNix

flake.nix

@@ -6,11 +6,20 @@
       inputs.nixpkgs.follows = "nixpkgs";
     };
     naersk.url = "github:nix-community/naersk";
-    flake-compat = { url = github:edolstra/flake-compat; flake = false; };
+    flake-compat = {
+      url = github:edolstra/flake-compat;
+      flake = false;
+    };
     flake-utils.url = "github:numtide/flake-utils";
   };
 
-  outputs = {nixpkgs, flake-utils, naersk, rust-overlay, ...}:
+  outputs = {
+    nixpkgs,
+    flake-utils,
+    naersk,
+    rust-overlay,
+    ...
+  }:
     flake-utils.lib.eachDefaultSystem (system: let
       overlays = [
         rust-overlay.overlays.default
@@ -26,17 +35,24 @@
         verion = "0.0.1";
         src = ./.;
         nativeBuildInputs = [pkgs.pkg-config];
-          buildInputs = (
+        buildInputs =
-            if pkgs.stdenv.isDarwin then
+          (
-              with pkgs.darwin.apple_sdk.frameworks; [ Security SystemConfiguration ]
+            if pkgs.stdenv.isDarwin
-            else
+            then with pkgs.darwin.apple_sdk.frameworks; [Security SystemConfiguration]
-            [ pkgs.openssl ]) ++ [rust-bin];
+            else [pkgs.openssl]
+          )
+          ++ [rust-bin];
       };
-    in
+    in {
-    {
       packages.default = heracles;
-    }) // {
+    })
-        nixosModule = {config, pkgs, lib}: with lib; {
+    // {
+      nixosModule = {
+        config,
+        pkgs,
+        lib,
+      }:
+        with lib; {
           options = {
             services.heracles.enable = mkEnableOption "enable heracles service";
             services.heracles.listen = mkOption {
@@ -134,7 +150,7 @@
 
           config = mkIf config.services.heracles.enable {
             environment.etc."heracles.yaml" = {
-                    text = (generators.toYAML {} config.services.heracles.settings);
+              text = generators.toYAML {} config.services.heracles.settings;
             };
             systemd.services.heracles = {
               wantedBy = ["multi-user.target" "default.target"];