The web test mock server now supports grouping dates by week and year, in addition to day and month. This helps internal tests better reflect real reporting behavior and ensures date filters use correct start and end dates.

Description of the issue/feature this PR addresses:
* Task: https://www.odoo.com/web?#id=29402&view_type=form&model=project.task&menu_id=5200
* Pad: https://pad.odoo.com/p/r.241110e82b471a377043ef793f229a50

Current behavior before PR:

Desired behavior after PR is merged:


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This update aligns several scheduling-related areas with Odoo's updated resource calendar API. It helps keep manufacturing work orders, project forecasting, timesheets, and website appointments working consistently with the shared calendar logic.

Adapt code to new API of resource calendar.

The settings screens for Timesheet Grid and Timesheet Sales were adjusted to stay aligned with related changes in the main Odoo settings structure. This keeps the billing-related options visible in the right place and helps prevent confusion when configuring timesheet invoicing features.

Task: https://www.odoo.com/web?#id=1841221&view_type=form&model=project.task&action=327&menu_id=4720
Pad: https://pad.odoo.com/p/r.6c2b07f6e9f0cad27d6d29500c090db8