fix(snake.cpp .hpp): first step to extracting tail functions and head movement to just head and tail separately

include/point.hpp

@@ -2,6 +2,7 @@
 #define POINT_HPP
 
 #include <array>
+#include <string>
 #include "globals.hpp"
 
 struct Point {
@@ -12,7 +13,6 @@ struct Point {
 
     std::string to_string() const;
     void clear(std::array<std::array<char, COL>, ROW> &arr) const;
-    void get_new_point(int direction);
 };
 
 #endif // POINT_HPP