docs(convert): moving the actual documentation on the header

- The documentation on the header allow u to see on the files where the
header is inclued

includes/convert.h

@@ -6,15 +6,35 @@
 /*   By: rparodi <rparodi@student.42.fr>            +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2024/10/31 14:57:24 by rparodi           #+#    #+#             */
-/*   Updated: 2025/09/01 17:55:58 by rparodi          ###   ########.fr       */
+/*   Updated: 2025/09/05 16:07:54 by rparodi          ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
 #ifndef CONVERT_H
 # define CONVERT_H
 
+/**
+ * @brief Converts integer to string
+ *
+ * @param n the integer that will be converted
+ * @return The string with this integer
+ */
 char			*ft_itoa(int n);
+
+/**
+ * @brief Converts string to integer
+ *
+ * @param nptr the string that will be converted
+ * @return The integer on the string
+ */
 int				ft_atoi(const char *nptr);
+
+/**
+ * @brief Converts string to long long integer
+ *
+ * @param nptr the string that will be converted
+ * @return The long long int on the string
+ */
 long long int	ft_atoll(const char *nptr);
 
 #endif