Update optimal_direction_simple

exercises/25/pacman_ai/solution/optimal_direction_simple

@@ -1 +1,13 @@
+Direction PacManAI::optimalDirection(const std::array<Move, 4> & moves) {
+  double closestDistance = std::numeric_limits<double>::infinity();
+  Direction dir = Direction::NONE;
 
+  for (const auto & move : moves) {
+    if (move.distanceToTarget < closestDistance) {
+      closestDistance = move.distanceToTarget;
+      dir = move.direction;
+    }
+  }
+
+  return dir;
+}