<b>Steps to reproduce :</b>

1) Install the Purchase module
2) Create and confirm a Purchase Order with a product and quantity 
3) From the Purchase Order, open the product and archive it

<b>Issue:</b>
Before archiving the product, the `Purchased` smart button correctly displays 
the total purchased quantity.

However, after archiving the product template, this smart button displays `0.0`, 
even though purchases exist.

Additionally, clicking the button opens a blank purchase order line view instead 
of showing related records if the product is archived.

<b>Cause:-</b>
Archiving a product template sets active=False on the template and its variants. 
The computed field `purchased_product_qty` relies on the variants to calculate the total. 
Because the variants are inactive post-archival, the compute method sees no records, 
resulting in a displayed value of 0.0.

Similarly, the smart button action uses the active variants in its domain, 
so it fails to find any related purchase order lines.

<b>Solution:</b>

The context is now explicitly set with active_test=False when computing 
the purchased_product_qty and when generating the domain for the smart button action.

This ensures that even inactive variants are included in the calculation and the view logic, 
preserving the correct purchased quantity and showing the relevant purchase lines after archival.

opw-4781578

Forward-Port-Of: odoo/odoo#209955

Currently, the VAT is split into two columns only if the VAT code
consists solely of numeric values. However, in practice, VAT code
may contain a combination of letters and numbers.

**Steps to reproduce :**

1) Install `l10n_de_reports` and switch to the `DE` company 
2) Create a partner with VAT as `NL000099998B57` from contacts
3) Now create a confirmed invoice for the above created partner
4) Go to "Accounting / Reporting / Audit Reports / General Ledger"
5) Download "DATEV DATA (ZIP)" and check "EXTF_customer_account.csv"

**Issue:**

Notice that the VAT was not split into country and VAT code for the above created partner.

**Cause:**

Previously, the code only split the VAT into country code and VAT code
if the first two characters were alphabetic and the remainder was numeric.

https://github.com/odoo/enterprise/blob/35944a38d306ea881e08e1d51ca77a3eab3a6e36/l10n_de_reports/models/datev_export_csv.py#L220-L227

This approach is insufficient because many countries have VAT codes that
include both letters and numbers.
For example vat formats for `NL` and `AT`
https://business.gov.nl/finance-and-taxes/vat/numbers-for-vat/
https://ec.europa.eu/taxation_customs/vies/#/faq

So by only checking whether the VAT code is numberic is not a valid thing.

**Solution:**

The code now uses the partner’s `_split_vat` method to separate the country code
and VAT code whenever a VAT is provided and has more than two characters.
It then validates the split VAT using the `simple_vat_check` helper method.

If the VAT is valid, the country code (in uppercase) and the VAT code are output
in separate columns; otherwise, the original VAT value is kept.

This change ensures that VAT numbers with alphanumeric codes are correctly
handled and split into their respective columns.


opw-4820929

Forward-Port-Of: odoo/enterprise#86992