Restore evicted owners from plans

- A demanded owner missing from the owner cache is restored from its planned tile (resident or prepared-plan store) instead of drafted again
- Same restore path as persisted tiles; plans identical

core/src/test/java/art/arcane/iris/generation/hydrology/HydrologyPlannerTest.java

@@ -133,6 +133,33 @@ public class HydrologyPlannerTest {
         assertTileContentsEqual(tile, planner.plan(EARLY_OWNER_TILE));
     }
 
+    @Test
+    public void evictedOwnerIsRestoredFromItsPlannedTileWithoutDrafting() {
+        AtomicInteger samples = new AtomicInteger();
+        HydrologyTerrainSampler counted = (int x, int z) -> {
+            samples.incrementAndGet();
+            return EARLY_OWNER_TERRAIN.sample(x, z);
+        };
+        HydrologyPlanner planner = new HydrologyPlanner(77L, EARLY_OWNER_SETTINGS, counted);
+        HydrologyTile tile = planner.plan(EARLY_OWNER_TILE);
+        CrossTileResolvedOwner original = tile.resolvedOwner();
+        planner.clearOwnerDrafts();
+        AtomicInteger lookups = new AtomicInteger();
+        planner.usePlannedTiles(key -> {
+            lookups.incrementAndGet();
+            return key.equals(EARLY_OWNER_TILE) ? tile : null;
+        });
+        samples.set(0);
+
+        CrossTileResolvedOwner restored = planner.resolveIndependentOwner(EARLY_OWNER_TILE);
+
+        assertEquals(original, restored);
+        assertEquals(0, samples.get());
+        assertEquals(1, lookups.get());
+        assertSame(restored, planner.resolveIndependentOwner(EARLY_OWNER_TILE));
+        assertEquals(1, lookups.get());
+    }
+
     @Test
     public void restoringPreparedTileKeepsExistingCanonicalOwner() {
         HydrologyPlanner planner = new HydrologyPlanner(77L, EARLY_OWNER_SETTINGS, EARLY_OWNER_TERRAIN);

core/src/test/java/art/arcane/iris/generation/hydrology/HydrologyTileCacheTest.java

@@ -38,6 +38,7 @@ import java.util.concurrent.TimeoutException;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
+import java.util.function.Function;
 import java.util.function.Predicate;
 import org.mockito.ArgumentCaptor;
 
@@ -45,6 +46,7 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
 import static org.mockito.ArgumentMatchers.any;
@@ -615,6 +617,25 @@ public class HydrologyTileCacheTest {
         verify(planner).limitEarlyOwners(null);
     }
 
+    @Test
+    @SuppressWarnings("unchecked")
+    public void plannerFindsTilesThisCachePlanned() {
+        HydrologyPlanner planner = mock(HydrologyPlanner.class);
+        HydrologyTile tile = mock(HydrologyTile.class);
+        HydrologyPlannerSettings settings = stalePrefetchSettings();
+        when(planner.settings()).thenReturn(settings);
+        when(planner.plan(any(HydrologyTileKey.class))).thenReturn(tile);
+        HydrologyTileCache cache = new HydrologyTileCache(planner, 128);
+        ArgumentCaptor<Function<HydrologyTileKey, HydrologyTile>> planned = ArgumentCaptor.forClass(Function.class);
+        verify(planner).usePlannedTiles(planned.capture());
+        HydrologyTileKey key = new HydrologyTileKey(3, -2);
+
+        assertNull(planned.getValue().apply(key));
+        assertSame(tile, cache.get(key));
+        assertSame(tile, planned.getValue().apply(key));
+        verify(planner, times(1)).plan(key);
+    }
+
     @Test
     public void invalidPregenBoundsLeaveQueuedPrefetchIntact() {
         HydrologyPlanner planner = mock(HydrologyPlanner.class);