Pad the answers PHP array with missing blank strings at the end

The $answers array needs to be padded at the end with blank strings that correspond with unrevealed clues. Otherwise, an undefined offset error will be thrown by PHP, leading to a syntax error in the generated JS code.

- When the foreach loop that populates the $answers array terminates early without completely filling this array with the necessary number of elements, the missing elements at the end are filled with blank strings.