refactor(signal): use native signal-cli service

systems/jeeves/docker/signal-cli-rest-api.nix

@@ -1,18 +0,0 @@
-let
-  vars = import ../vars.nix;
-in
-{
-  virtualisation.oci-containers.containers.signal_cli_rest_api = {
-    image = "bbernhard/signal-cli-rest-api:0.199-dev";
-    ports = [
-      "8989:8080"
-    ];
-    volumes = [
-      "${vars.docker_configs}/signal-cli-config:/home/.local/share/signal-cli"
-    ];
-    environment = {
-      MODE = "json-rpc";
-    };
-    autoStart = true;
-  };
-}