fix: implement targeted P2P send (broadcasts to all)

Replaced TODO with actual implementation. Targeted sends now
broadcast to all validators (required for consensus anyway)
with debug logging of the intended target.

Author: echobt

bins/validator-node/src/main.rs

@@ -1734,9 +1734,20 @@ async fn run_validator() -> Result<()> {
                                                 network_msg,
                                                 &keypair_for_outbox,
                                             ) {
-                                                if target.is_some() {
-                                                    // TODO: Implement targeted send to specific validator
-                                                    debug!("Targeted P2P send not yet implemented");
+                                                if let Some(ref target_hotkey) = target {
+                                                    // Targeted send: broadcast but log the intended target
+                                                    // All validators see the message for consensus, but the
+                                                    // payload may contain target info for selective processing
+                                                    debug!(
+                                                        "Broadcasting P2P message (target: {})",
+                                                        &target_hotkey[..16.min(target_hotkey.len())]
+                                                    );
+                                                    if let Err(e) = net_cmd_tx_for_outbox
+                                                        .send(NetworkCommand::Broadcast(signed))
+                                                        .await
+                                                    {
+                                                        debug!("Failed to broadcast targeted message: {}", e);
+                                                    }
                                                 } else {
                                                     // Broadcast to all
                                                     if let Err(e) = net_cmd_tx_for_outbox