luci-app-argon-config/root/usr/share/rpcd/acl.d/luci-app-argon-config.json

{
    "luci-argon-config": {
        "description": "Luci Argon theme config ",
        "read": {
            "uci": [ "argon" ]
        },
        "write": {
            "uci": [ "argon" ]
        }
    }
}