Check spawned worker version vs node version before PVF preparation (#6861)

* Check spawned worker version vs node version before PVF preparation

* Address discussions

* Propagate errors and shutdown preparation and execution pipelines properly

* Add logs; Fix execution worker checks

* Revert "Propagate errors and shutdown preparation and execution pipelines properly"

This reverts commit b96cc3160ff58db5ff001d8ca0bfea9bd4bdd0f2.

* Don't try to shut down; report the condition and exit worker

* Get rid of `VersionMismatch` preparation error

* Merge master

* Add docs; Fix tests

* Update Cargo.lock

* Kill again, but only the main node process

* Move unsafe code to a common safe function

* Fix libc dependency error on MacOS

* pvf spawning: Add some logging, add a small integration test

* Minor fixes

* Restart CI

---------

Co-authored-by: Marcin S <marcin@realemail.net>

polkadot/node/core/pvf/tests/it/worker_common.rs

@@ -18,6 +18,15 @@ use crate::PUPPET_EXE;
 use polkadot_node_core_pvf::testing::worker_common::{spawn_with_program_path, SpawnErr};
 use std::time::Duration;
 
+// Test spawning a program that immediately exits with a failure code.
+#[tokio::test]
+async fn spawn_immediate_exit() {
+	let result =
+		spawn_with_program_path("integration-test", PUPPET_EXE, &["exit"], Duration::from_secs(2))
+			.await;
+	assert!(matches!(result, Err(SpawnErr::AcceptTimeout)));
+}
+
 #[tokio::test]
 async fn spawn_timeout() {
 	let result =