Update nix file

.idx/dev.nix

@@ -1,24 +1,24 @@
-{pkgs}: {
+{ pkgs, ... }: {
   channel = "stable-23.11";
   packages = [
     pkgs.nodejs_20
   ];
-  idx.extensions = [];
+  env = {};
-  idx.previews = {
+  idx = {
+    extensions = [];
+    workspace = {
+      onCreate = {
+        npm-install = "npm install";
+      };
+    };
     previews = {
-      web = {
+      enable = true;
-        command = [
+      previews = {
-          "npm"
+        web = {
-          "run"
+          command = ["npm" "run" "dev" "--" "--port" "$PORT" "--host" "0.0.0.0"];
-          "dev"
+          manager = "web";
-          "--"
+        };
-          "--port"
-          "$PORT"
-          "--host"
-          "0.0.0.0"
-        ];
-        manager = "web";
       };
     };
   };
-}
+}