[hal,sim] Add notifier generation counter to WaitForProgramStart (#8947)

This fixes simulation WaitForProgramStart(true) potentially advancing
due to a stale or pre-start notifier created before SetProgramStarted()
was called.

hal/src/main/native/sim/NotifierInternal.hpp

@@ -4,10 +4,13 @@
 
 #pragma once
 
+#include <stdint.h>
+
 namespace wpi::hal {
 void PauseNotifiers();
 void ResumeNotifiers();
 void WakeupNotifiers();
 void WaitNotifiers();
 void WakeupWaitNotifiers();
+uint64_t GetNotifierAlarmSetCount();
 }  // namespace wpi::hal