Poll instead of sleeping

- Add the Await test helper that polls a condition every ten milliseconds under a bounded timeout
- Replace every Thread.sleep in the fourteen polling test classes with a condition wait, a latch wait or a bounded quiet window
- Keep the crash-consistency fsync interception in GenerationHistoryAdmissionTest and SavedBiomeStoreBatchTest on real barriers

adapters/bukkit/nms/v26_2_R1/src/test/java/art/arcane/iris/nativegen/NativeStructureVolumeIndexTest.java

@@ -32,6 +32,7 @@ import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.locks.LockSupport;
 import java.util.function.IntConsumer;
 
 import static org.junit.Assert.assertEquals;
@@ -218,7 +219,7 @@ public class NativeStructureVolumeIndexTest {
                     if (cleared) {
                         break;
                     }
-                    Thread.sleep(1);
+                    LockSupport.parkNanos(TimeUnit.MILLISECONDS.toNanos(10L));
                 }
                 assertTrue("Origin eviction did not complete before the query cache lock", cleared);
                 resolver.release();