Palette section buffer

- Add SectionBuffer: chunk palette of written instances and short[4096] ids per section in y, z, x order
- Column tops are indexed per x-slice and padded so fan-out slices do not share a cache line
- Add ColumnRunHunk and forward column runs through the listening hunk and block update listener
- Terrain painter emits column runs and evaluates ores only inside the column's ore bands
- Bukkit generation writes into SectionBuffer and applies it through ChunkDataOutput
- Remove ChunkDataHunkHolder and the probe's ProductionBlockHunk copy
- Probe production buffers use SectionBuffer

probe/src/test/java/art/arcane/iris/probe/ProductionHunkTest.java

@@ -1,5 +1,6 @@
 package art.arcane.iris.probe;
 
+import art.arcane.iris.generation.chunk.SectionBuffer;
 import art.arcane.volmlib.nativelib.terrain.NativeBiome;
 import art.arcane.volmlib.nativelib.terrain.NativeBlockState;
 import art.arcane.volmlib.util.hunk.Hunk;
@@ -19,7 +20,7 @@ public final class ProductionHunkTest {
 
     @Test
     public void blockHunkIgnoresNullWritesAndTracksTheHighestStoredCellPerColumn() {
-        ProductionBlockHunk blocks = new ProductionBlockHunk(HEIGHT);
+        SectionBuffer blocks = new SectionBuffer(HEIGHT);
         NativeBlockState stone = StubPlatform.blockStateForTest("minecraft:stone");
         NativeBlockState dirt = StubPlatform.blockStateForTest("minecraft:dirt");
 
@@ -37,7 +38,7 @@ public final class ProductionHunkTest {
 
     @Test
     public void dumpCaptureOfTheBlockHunkMatchesAnArrayHunkHoldingTheSameWrites() {
-        ProductionBlockHunk production = new ProductionBlockHunk(HEIGHT);
+        SectionBuffer production = new SectionBuffer(HEIGHT);
         Hunk<NativeBlockState> array = Hunk.newArrayHunk(16, HEIGHT, 16);
         Hunk<NativeBiome> biomes = Hunk.newArrayHunk(16, HEIGHT, 16);
         NativeBlockState stone = StubPlatform.blockStateForTest("minecraft:stone");