feat(world): Parkwege, Felder, Plätze, Pool und Parkplatz als eigene Schichten

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/world/streaming.js

@@ -4,7 +4,7 @@ import { buildChunkGeometry } from "./geometry.js";
 import { pointInPolygon } from "./props.js";
 
 const key = (i, j) => `${i}_${j}`;
-const DECALS = new Set(["roads", "sand", "park", "urban"]);
+const DECALS = new Set(["roads", "sand", "park", "urban", "field", "court", "pool", "parking", "paths"]);
 
 /** Mittelpunkt eines Chunks in three-Koordinaten. */
 function chunkCenter(i, j) {