nixos/warpgate: add `log.audit_retention`

                  "json"

                ];

              };

              audit_retention = mkOption {

                description = "How long Warpgate keeps its audit logs.";

                default = "1year";

                type = str;

              };

              retention = mkOption {

                description = "How long Warpgate keep its logs.";

                description = "How long Warpgate keeps its non-audit logs and session recordings.";

                default = "7days";

                type = str;

              };