warn for not using local stacks node with the signer

stacks-signer/src/main.rs

@@ -35,10 +35,10 @@ use clap::Parser;
 use clarity::vm::types::QualifiedContractIdentifier;
 use libsigner::{RunningSigner, Signer, SignerEventReceiver, SignerSession, StackerDBSession};
 use libstackerdb::StackerDBChunkData;
-use slog::{slog_debug, slog_info};
+use slog::{slog_debug, slog_info, slog_warn};
 use stacks_common::util::hash::to_hex;
 use stacks_common::util::secp256k1::{MessageSignature, Secp256k1PublicKey};
-use stacks_common::{debug, info};
+use stacks_common::{debug, info, warn};
 use stacks_signer::cli::{
     Cli, Command, GenerateStackingSignatureArgs, GetChunkArgs, GetLatestChunkArgs, PutChunkArgs,
     RunSignerArgs, StackerDBArgs,
@@ -81,6 +81,12 @@ fn write_chunk_to_stdout(chunk_opt: Option<Vec<u8>>) {
 fn spawn_running_signer(path: &PathBuf) -> SpawnedSigner {
     let config = GlobalConfig::try_from(path).unwrap();
     let endpoint = config.endpoint;
+    warn!(
+        "Reminder: The signer is primarily designed for use with a local or subnet network stacks node. \
+        It's important to exercise caution if you are communicating with an external node, \
+        as this could potentially expose sensitive data or functionalities to security risks \
+        if additional proper security checks are not integrated in place."
+    );
     info!("Starting signer with config: {}", config);
     let (cmd_send, cmd_recv) = channel();
     let (res_send, res_recv) = channel();