feat: Add state version

configuration.nix

@@ -89,6 +89,7 @@ in
     allowReboot = config.services.userdata.autoUpgrade.allowReboot;
     channel = "https://channel.selfprivacy.org/nixos-selfpricacy";
   };
+  system.stateVersion = config.services.userdata.stateVersion;
   nix = {
     optimise.automatic = true;
     gc = {

variables-module.nix

@@ -41,6 +41,13 @@ in
         type = types.nullOr types.bool;
       };
     };
+    stateVersion = mkOption {
+      description = ''
+        State version of the server
+      '';
+      type = types.string;
+      default = "22.11";
+    };
     ########################
     # Server admin options #
     ########################

variables.nix

@@ -7,6 +7,7 @@ in
     hostname = lib.attrsets.attrByPath [ "hostname" ] null jsonData;
     domain = lib.attrsets.attrByPath [ "domain" ] null jsonData;
     timezone = lib.attrsets.attrByPath [ "timezone" ] "Europe/Uzhgorod" jsonData;
+    stateVersion = lib.attrsets.attrByPath [ "stateVersion" ] "22.05" jsonData;
     autoUpgrade = {
       enable = lib.attrsets.attrByPath [ "autoUpgrade" "enable" ] true jsonData;
       allowReboot = lib.attrsets.attrByPath [ "autoUpgrade" "allowReboot" ] true jsonData;