Add system.configurationRevision to configuration.nix and tidy flake.nix

configuration.nix

@@ -112,6 +112,8 @@
   #
   # For more information, see `man configuration.nix` or https://nixos.org/manual/nixos/stable/options#opt-system.stateVersion .
 
+
+  system.configurationRevision = lib.mkIf (specialArgs.inputs.self ? rev) specialArgs.inputs.self.rev;
   system.stateVersion = "25.05"; # Did you read the comment?
 }
 

flake.nix

@@ -17,6 +17,7 @@
           # pass flake inputs to individual module files
           specialArgs = { inherit inputs; };
         } // args));
+       
     in {
 
       packages."${system}".default =