YITH WooCommerce PDF Invoice 4.25.0

* New: support for WooCommerce 9.5
* Update: YITH plugin framework
* Fix: css align search box in documents table
* Dev: register correctly metas with the checkout block

* New: support for WooCommerce 8.6
* Update: YITH plugin framework
* Dev: added new filter yith_ywpi_product_item_metadata'
* Dev: added the yith_ywpi_apply_old_percentage_tax_calculation filter in the XML tax calculation
* Dev: added the placeholder parent_invoice_number in the document number block, to display the invoice number in the credit notes
* Dev: changed to public attribute
* Dev: minor change in a condition to check if the HPOS is enabled

* Update: YITH plugin framework
* Tweak: removed unnecessary conditions for the regular price retrieval in the invoices