BoardBehavior : add the documentation

src/main/java/model/BoardBehavior.java

 package model;
 
 import util.Position;
-
 import java.util.List;
 
-public interface BoardBehavior {
-    public int stepNumber(); // Numéro de l'étape actuelle.
-   public List<Position> updateToNextGeneration();
-   public void reset();
+public interface BoardBehavior<S> {
+    /**
+     * Get the current step number or generation of the board.
+     *
+     * @return The current step number or generation.
+     */
+    int stepNumber();
+
+    /**
+     * Update the board to its next generation or state. This method may modify the
+     * internal state of the board and return a list of positions that have changed
+     * during the update.
+     *
+     * @return A list of positions that have changed during the update.
+     */
+    List<Position> updateToNextGeneration();
+
+    /**
+     * Reset the board to its initial state.
+     */
+    void reset();
 }