New `public_administration` field on Customers endpoints

The response of the customers endpoints now includes a public_administration boolean for company customers. It returns true when the customer is a French public administration.

Use this field to find public administrations before you convert an invoice to an e-invoice. A null electronic_billing_address does not tell you whether the customer is a public administration.

Impacted endpoints:

• List customers (company and individual)
• Retrieve a customer
• Create a customer (company or individual)
• Update a customer (company or individual)

This is a non-breaking change. The new field is additional and does not affect the existing response structures.