The GSTR return period form now hides the tax unit option when no tax unit is available. This keeps the form cleaner and avoids showing users an irrelevant choice.

In this PR
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**[IMP] l10n_in_reports_gstr: hide tax unit if not available**
- This commits hides the tax unit for gstr return period form if no tax unit is available

task-3679488

The online sales templates for rentals and subscriptions were simplified after related product page caching was removed. This keeps the website sales experience aligned with platform changes and should make future maintenance easier without changing visible business workflows.

Now that the cache has been removed from product page, those templates (or part of) can be simplified.

See also:
https://github.com/odoo/odoo/pull/145532
https://github.com/odoo/upgrade/pull/5422

This update removes two outdated account codes (999001 and 999002) from the Bulgarian financial reports that were previously used to categorize extraordinary income and expenses. This ensures the profit and loss reports now accurately reflect the current chart of accounts structure used in Bulgaria.

999001 and 999002 are no longer used for extraordinary income/expenses.
This commit removes them from the domains of the corresponding report.

Task ID: 3672294

Forward-Port-Of: odoo/enterprise#55022
Forward-Port-Of: odoo/enterprise#54491