flake: update nixpkgs, add formatter, run nix fmt

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

flake.lock

@@ -2,11 +2,11 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1743583204,
-        "narHash": "sha256-F7n4+KOIfWrwoQjXrL2wD9RhFYLs2/GGe/MQY1sSdlE=",
+        "lastModified": 1772963539,
+        "narHash": "sha256-9jVDGZnvCckTGdYT53d/EfznygLskyLQXYwJLKMPsZs=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "2c8d3f48d33929642c1c12cd243df4cc7d2ce434",
+        "rev": "9dcb002ca1690658be4a04645215baea8b95f31d",
         "type": "github"
       },
       "original": {

flake.nix

@@ -51,6 +51,8 @@
         };
       };
 
+      formatter = forAllSystems ({ pkgs, ... }: pkgs.nixfmt-tree);
+
       packages = forAllSystems (
         { pkgs }:
         {

pkgs/path-of-building-poe2/default.nix

@@ -64,7 +64,8 @@ stdenv.mkDerivation {
     qttools
     wrapQtAppsHook
     icoutils
-  ] ++ lib.optional stdenv.hostPlatform.isLinux copyDesktopItems;
+  ]
+  ++ lib.optional stdenv.hostPlatform.isLinux copyDesktopItems;
 
   buildInputs = [
     qtbase

pkgs/vintagestory/default.nix

@@ -75,8 +75,7 @@ stdenv.mkDerivation rec {
     runHook postInstall
   '';
 
-  preFixup =
-    ''
+  preFixup = ''
     sed -i 's/net7.0/net8.0/' $out/share/vintagestory/Vintagestory.runtimeconfig.json
     sed -i 's/7.0.0/8.0.11/' $out/share/vintagestory/Vintagestory.runtimeconfig.json