Steps to reproduce the issue

When creating a schemaorg plugin for an element containing offers, it is not possible to specify a price value of 0 - it is deleted

Expected result

"offers": { "@type": "Offer", "price": "0", "priceCurrency": "USD" }

Actual result

"offers": { "@type": "Offer", "priceCurrency": "USD" }

System information (as much as possible)

Joomla 5.1
Php 8.2

Additional comments

Google allow value 0 for show "Price: free" (https://developers.google.com/search/docs/appearance/structured-data/software-app?hl=en)

Lines causing the error

plugins/system/schemaorg/src/Extension/Schemaorg.php : cleanupSchema
if (empty($value)) { continue; }