Test timing freshness gate

- Test that capture drops generation timings once generation is idle
- Test that capture carries the engine timing averages while fresh
- Remove the hand-built idle snapshot test that passed without the gate

adapters/bukkit/plugin/src/test/java/art/arcane/iris/integration/IrisIntegrationServiceTest.java

@@ -97,26 +97,6 @@ public class IrisIntegrationServiceTest {
         assertFalse(nether.samples().get(IntegrationMetricSchema.IRIS_PREGEN_REMAINING).available());
     }
 
-    @Test
-    public void idleWorldsPublishGenerationTimingsAsUnavailable() {
-        long now = System.currentTimeMillis();
-        EngineTelemetrySnapshot idle = new EngineTelemetrySnapshot(
-                now, "minecraft:overworld", "world", "dimension", true, false, false, false,
-                12L, 3L, 0.25D, 20L, 20L, 0D, 0L, 2, 0, 1L, 4L, 1L, 10D, Map.of());
-        IrisIntegrationService service = new IrisIntegrationService(
-                () -> telemetry(List.of(idle), IrisTelemetrySnapshot.PregenSnapshot.INACTIVE, now)
-        );
-
-        IntegrationMetricSample total = service.sampleMetrics(Set.of(IntegrationMetricSchema.IRIS_GENERATION_TOTAL_MS))
-                .get(IntegrationMetricSchema.IRIS_GENERATION_TOTAL_MS);
-        IntegrationMetricSample worldTotal = service.metricGroups().get(0).samples()
-                .get(IntegrationMetricSchema.IRIS_GENERATION_TOTAL_MS);
-
-        assertFalse(total.available());
-        assertEquals("timing-not-available", total.message());
-        assertFalse(worldTotal.available());
-    }
-
     @Test
     public void publishesEveryManagedWorldWithoutAWorldCountCap() {
         long now = System.currentTimeMillis();

core/src/test/java/art/arcane/iris/generation/runtime/EngineTelemetrySnapshotTest.java

@@ -7,6 +7,9 @@ import java.util.List;
 import java.util.Map;
 
 import static org.junit.Assert.assertEquals;
+import static org.mockito.Mockito.RETURNS_DEEP_STUBS;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
 
 public class EngineTelemetrySnapshotTest {
     @Test
@@ -138,6 +141,33 @@ public class EngineTelemetrySnapshotTest {
         assertEquals(1, EngineTelemetrySnapshot.aggregate(snapshots).worldCount());
     }
 
+    @Test
+    public void captureLeavesOutGenerationTimingsOnceGenerationHasGoneIdle() {
+        Engine engine = engineWithTimings(Map.of("total", 12D, "terrain", 4D));
+
+        EngineTelemetrySnapshot snapshot = EngineTelemetrySnapshot.capture(engine, 0D, false, 5_000L);
+
+        assertEquals(Map.of(), snapshot.generationTimingsMs());
+    }
+
+    @Test
+    public void captureCarriesTheEngineTimingAveragesWhileGenerationIsFresh() {
+        Engine engine = engineWithTimings(Map.of("total", 12D, "terrain", 4D));
+
+        EngineTelemetrySnapshot snapshot = EngineTelemetrySnapshot.capture(engine, 3D, true, 5_000L);
+
+        assertEquals(Map.of("total", 12D, "terrain", 4D), snapshot.generationTimingsMs());
+        assertEquals(3D, snapshot.chunksPerSecond(), 0D);
+    }
+
+    private static Engine engineWithTimings(Map<String, Double> averages) {
+        Engine engine = mock(Engine.class, RETURNS_DEEP_STUBS);
+        when(engine.getWorld().identity()).thenReturn("minecraft:overworld");
+        when(engine.getWorld().name()).thenReturn("world");
+        when(engine.getMetrics().telemetryAverages()).thenReturn(averages);
+        return engine;
+    }
+
     private static EngineTelemetrySnapshot snapshot(
             String identity,
             String name,