derive default layers, armor wearers, arms/chest pose flags and mob variant textures from the vanilla dump, drop the hardcoded lists

src/main/java/eu/mhsl/minecraft/pixelpics/Main.java

@@ -14,6 +14,7 @@ import eu.mhsl.minecraft.pixelpics.render.RenderManager;
 import eu.mhsl.minecraft.pixelpics.render.entity.cem.BlockEntityBaker;
 import eu.mhsl.minecraft.pixelpics.render.entity.cem.CemBaker;
 import eu.mhsl.minecraft.pixelpics.render.entity.cem.CemModelLoader;
+import eu.mhsl.minecraft.pixelpics.render.entity.cem.DatapackVariants;
 import eu.mhsl.minecraft.pixelpics.render.render.DefaultScreenRenderer;
 import eu.mhsl.minecraft.pixelpics.render.tint.BiomeTintProvider;
 import eu.mhsl.minecraft.pixelpics.survival.CameraListener;
@@ -23,6 +24,8 @@ import eu.mhsl.minecraft.pixelpics.survival.SurvivalRecipes;
 import eu.mhsl.minecraft.pixelpics.utils.MapColorPalette;
 import java.io.File;
 import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Objects;
 import java.util.Optional;
 import org.bukkit.Bukkit;
@@ -121,6 +124,10 @@ public final class Main extends JavaPlugin {
         } catch (Exception e) {
             getLogger().severe("Failed to load vanilla entity models: " + e.getMessage());
         }
+        List<File> worldFolders = new ArrayList<>();
+        for (org.bukkit.World w : getServer().getWorlds()) worldFolders.add(w.getWorldFolder());
+        int datapackVariants = DatapackVariants.load(cemLoader, worldFolders, getLogger());
+        if (datapackVariants > 0) getLogger().info("Loaded " + datapackVariants + " datapack mob variants.");
         SkinCache skinCache = new SkinCache();
         BitmapFont font = FontLoader.load(resourcePack, textures, getLogger());
         getLogger().info("Loaded sign font (" + (font.isEmpty() ? "no glyphs — text disabled" : "ok") + ").");