Propagate cancel token to mixnet client

Cargo.lock

@@ -5746,7 +5746,6 @@ dependencies = [
  "criterion",
  "ff",
  "group",
- "lazy_static",
  "nym-contracts-common",
  "nym-pemstore",
  "rand 0.8.5",

nym-registration-client/src/builder/config.rs

@@ -4,7 +4,8 @@
 use nym_credential_storage::persistent_storage::PersistentStorage;
 use nym_registration_common::NymNode;
 use nym_sdk::{
-    DebugConfig, NymNetworkDetails, RememberMe, TopologyProvider, UserAgent,
+    DebugConfig, NymNetworkDetails, RememberMe, ShutdownToken, ShutdownTracker, TopologyProvider,
+    UserAgent,
     mixnet::{
         CredentialStorage, GatewaysDetailsStore, KeyStore, MixnetClient, MixnetClientBuilder,
         MixnetClientStorage, OnDiskPersistent, ReplyStorageBackend, StoragePaths, x25519::KeyPair,
@@ -115,7 +116,10 @@ impl BuilderConfig {
             .debug_config(debug_config)
             .credentials_mode(true)
             .with_remember_me(remember_me)
-            .custom_topology_provider(self.custom_topology_provider);
+            .custom_topology_provider(self.custom_topology_provider)
+            .custom_shutdown(ShutdownTracker::new_from_external_shutdown_token(
+                ShutdownToken::from(self.cancel_token),
+            ));
 
         #[cfg(unix)]
         let builder = builder.with_connection_fd_callback(self.connection_fd_callback);