Zebby VAT Validation for WooCommerce

Adds a VAT field to the WooCommerce checkout page (both classic and blocks). Validates the entered VAT number using the Zebby VAT API (https://api.zebby.io) and displays the result. Optionally allows for VAT exemption based on validation status and country rules.

Features:
* Adds VAT field to classic & block checkout.
* Real-time validation via AJAX (configurable).
* Displays validation success/failure/error messages.
* Displays company name if provided by API.
* Configurable API key and endpoint URL.
* Option to enforce VAT field requirement.
* Option to enable automatic VAT exemption for valid numbers in specific countries.
* Dedicated settings page.
* Debug logging option.

Data Sent to Zebby API

This plugin sends the following data to the Zebby VAT API for validation purposes:
– VAT number (required for validation)
– Country code (to determine applicable VAT rules)
– (Optionally) Company name, if provided by the user

This data is used solely to validate the VAT number and determine VAT exemption eligibility during checkout. No other personal or sensitive data is sent.