Feature/cancellation migration (#6014)

* squashing work on using cancellation in nym crates

making nym-task wasm compilable

removed sending of status messages

replaced TaskManager with ShutdownManager in the validator rewarder

additional helpers for ShutdownManager

simplified ShutdownToken by removing the name field

TaskClient => ShutdownToken within all client tasks

wip: remove TaskHandle

* track all long-living client tasks

* add task tracking for most top level tasks within nym-node

* improved default builder

* split up cancellation module

* module documentation and unit tests

* nym node fixes and naming consistency

* wasm fixes

* assert_eq => assert

* wasm fixes and made 'run_until_shutdown' take reference instead of ownership

* linux-specific fixes to IpPacketRouter

* post rebasing fixes for signing monitor

* add ShutdownManager constructor to build it from an external token

* applying PR review suggestions

nym-api/src/node_performance/contract_cache/mod.rs

@@ -45,7 +45,7 @@ pub(crate) async fn start_cache_refresher(
     .with_update_fn(move |main_cache, update| {
         refresher_update_fn(main_cache, update, values_to_retain)
     })
-    .start(shutdown_manager.clone_token("performance-contract-cache-refresher"));
+    .start(shutdown_manager.clone_shutdown_token());
 
     Ok(warmed_up_cache)
 }