Added alejandra formatter to neovim

modules/neovim/home.nix

@@ -113,6 +113,22 @@
           check_ts = true; # Use treesitter to avoid pairing inside strings/comments
         };
       };
+      conform-nvim = {
+        enable = true;
+        settings = {
+          formatters_by_ft = {
+            nix = ["alejandra"];
+          };
+          format_on_save = {
+            lsp_format = "fallback";
+            timeout_ms = 500;
+          };
+        };
+        # Pin the exact binary path so Nix guarantees it's available
+        settings.formatters = {
+          alejandra.command = "${pkgs.alejandra}/bin/alejandra";
+        };
+      };
     };
 
     extraPlugins = with pkgs.vimPlugins; [