[E-Documents Core] - Peppol BIS3.0 validation errors (when both the VAT and the invoice amount are zero)

[GMatuleviciute]

This pull request does not have a related issue as it's part of the delivery for development agreed directly with @altotovi @Groenbech96

Implementation

This update resolves an issue with generating the correct PEPPOL file when both the VAT and the invoice amount are zero. It introduces new validations during the posting of sales documents to ensure that the resulting PEPPOL file complies with tax category rules for services:

• For document lines with a zero VAT tax category, the system checks that the VAT percentage is 0.
• For document lines with a standard VAT tax category, the system verifies that the VAT percentage is greater than 0.
• For document lines with an outside VAT tax category, the system ensures that only one VAT breakdown line is created in the PEPPOL file.

Related Base App PR: https://github.com/microsoft/BusinessCentralApps/pull/1291

Fixes #

[github-actions]

Could not find linked issues in the pull request description. Please make sure the pull request description contains a line that contains 'Fixes #' followed by the issue number being fixed. Use that pattern for every issue you want to link.