JSON and fonts

Font-loader uses javascript to lazy load fonts.

For it to work, it need as json referecing the file and meta data.

If you make custom listing of font families, you need to make sure the page has the meta data JSON stored in the page.

`<?php if ( $fontFiles = $page->getFontFiles( $page->fontsFeat()->toPages() ) ) : ?>

<?php foreach ( $page->fontsFeat()->toPages() as $family ) : ?>
    <?php foreach ( $family->fonts() as $font ) : ?>
        <?php $fontFiles->add( $font->preview()->font() ) ?>
    <?php endforeach ?>
<?php endforeach ?>
<?= $page->getFontJson( $fontFiles ) ?>

<?php endif ?>`