feat: Server monitroing, NixOS 24.05 (#84)

Co-authored-by: nhnn <nhnn@disroot.org>
Reviewed-on: https://git.selfprivacy.org/SelfPrivacy/selfprivacy-nixos-config/pulls/84

configuration.nix

@@ -27,15 +27,12 @@ in
     # ./resources/limits.nix
   ];
 
-  # We have to use this version to be able to migrate from Gitea.
-  nixpkgs.config.permittedInsecurePackages = [
-    "forgejo-1.20.6-1-unstable-2024-04-18"
-  ];
-
   fileSystems."/".options = [ "noatime" ];
 
   services.selfprivacy-api.enable = true;
 
+  services.redis.package = pkgs.valkey;
+
   services.redis.servers.${redis-sp-api-srv-name} = {
     enable = true;
     save = [