This update improves the explanatory tooltips around accounting lock dates so users better understand how restrictions apply. It also reorganizes related lock-date validation into a dedicated module, making the behavior easier to maintain without changing the business workflow.

-task: https://www.odoo.com/web#id=38178&view_type=form&model=project.task&action=333&active_id=967&menu_id=4720

Description of the issue/feature this PR addresses:

Current behavior before PR:

Desired behavior after PR is merged:


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The test mail setup now uses production-like email alias settings during automated checks. This helps ensure mail-related behavior is validated more accurately and may also make some performance measurements more efficient.

Odoo will no longer generate translation data for languages that are marked as not translatable. This reduces unnecessary processing and helps keep translation handling cleaner without changing normal user workflows.

Followup of #9479