Returns are now created only when their deadlines are relevant: not before the company account opening date and within the next year. This helps avoid unnecessary or outdated return records and keeps Belgian reporting data clearer, with a minor wording correction for the Belgian collection center name.

Now, before generating a return, we compute the deadline of that return.
If the return is before the account opening date, we do not generate it.
We also only keep return with a deadline within a year from now.

In continuation of https://github.com/odoo/enterprise/pull/81569

Users can now open return attachments directly in a preview instead of downloading them first. This makes reviewing related documents faster and keeps the workflow smoother within Odoo.

Clicking on an attachment should preview the attachment without downloading.

task-4627315