Account Invoice Import Facturae

This module extends the invoice import wizard so that Odoo can read supplier invoices and refunds issued in the Spanish Facturae XML format. When you upload a Facturae file through the standard invoice import screen, the system recognises the format and fills in the vendor bill for you.

What it does automatically: - Validates the XML against the official Facturae schema and verifies the digital signature when one is present. - Reads the supplier's tax number and country, completing the VAT with the country prefix when needed. - Creates the invoice with its number, issue date, currency, untaxed total and total amount. - Creates the invoice lines with product code, description, quantity, unit price and taxes, including withheld taxes as negative percentages. - Decides whether the document is a supplier invoice or a supplier refund based on the invoice class.

Business rules and limits: - Invoices marked as 'lots' modality are rejected with an error. - Only Facturae versions 3.2, 3.2.1 and 3.2.2 are recognised; other XML files are passed to the standard import logic. - The Python library xmlsig is required for signature verification.

The module works on the account.invoice.import wizard and relies on the Spanish Facturae localisation for the schema files. It does not add new menus or screens of its own.