Entity Schema - Add domain support for the 'Required' Attribute

[cedricfrancoys]

Add support for the required attribute in fields should be flexible, allowing it to be defined either as a boolean or a domain expression:

• Boolean: A simple true or false setting, which universally mandates or waives the requirement for data entry.
• Domain: A more complex condition that specifies when a field becomes mandatory, based on the logic defined within the domain expression. This approach allows for conditional requirements that adapt to the data context or specific business rules.