Silence javac deprecation/unchecked notes

- GenericVector.toList(): replace deprecated DefaultGroovyMethods.toList
  (Groovy 5) with a plain Java loop; drop unused addTo() (no callers)
- Atoms(List<? extends Atom>): @SuppressWarnings("unchecked") for the
  intentional wrap-without-copy
- KdNode.splitLeafNode: @SuppressWarnings("unchecked") for casts from
  the Object[] backing store

src/main/groovy/cz/siret/prank/features/generic/GenericVector.java

@@ -1,7 +1,6 @@
 package cz.siret.prank.features.generic;
 
-import org.codehaus.groovy.runtime.DefaultGroovyMethods;
-
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 
@@ -61,13 +60,11 @@ public class GenericVector {
     }
 
     public List<Double> toList() {
-        return DefaultGroovyMethods.toList(data);
-    }
-
-    public void addTo(List<Double> list) {
-        for (int i = 0; i != data.length; i++) {
-            list.add(data[i]);
+        List<Double> list = new ArrayList<>(data.length);
+        for (double v : data) {
+            list.add(v);
         }
+        return list;
     }
 
     /**

src/main/groovy/cz/siret/prank/geom/Atoms.java

@@ -44,6 +44,7 @@ public final class Atoms implements Iterable<Atom> {
         list = new ArrayList<>(initialCapacity);
     }
 
+    @SuppressWarnings("unchecked")
     public Atoms(List<? extends Atom> list) {
         if (list == null) throw new AssertionError();
         this.list = (List<Atom>) list;

src/main/groovy/cz/siret/prank/geom/kdtree/thirdgen/KdNode.java

@@ -161,6 +161,7 @@ class KdNode<T> {
         return true;
     }
 
+    @SuppressWarnings("unchecked")
     private void splitLeafNode() {
         right = new KdNode<T>(dimensions, bucketCapacity);
         left = new KdNode<T>(dimensions, bucketCapacity);