The server now provides a standard signal for custom code to know when the system registry has finished loading. This helps multiprocessing deployments and external customizations coordinate startup more reliably without changing user-facing workflows.

**Description of the issue/feature this PR addresses:**
During multiprocessing we should have an event to patch into to wait for the registry to be loaded. This adds an event that's easy to inherit and implement in external customizations.

--
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr

The Sales app’s report layout category list has been improved to make report sections easier to view and manage. This helps users organize sales document layouts more clearly with a small usability enhancement.

Project kanban cards now show their action links in more consistent positions, making the dashboard easier to scan and use. The update adjusts how project, timesheet, and sales-timesheet links are laid out so card content no longer shifts unpredictably.

Description of the issue/feature this PR addresses:

Current behavior before PR:

Desired behavior after PR is merged:




--
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr

Vendor bill and employee expense forms now include a dedicated space where attachment previews can be shown. This prepares the interface for a follow-up enhancement that will let users preview related documents directly from the side panel.

Task: https://www.odoo.com/web?#id=40663&view_type=form&model=project.task&action=333&active_id=131&menu_id=4720
PAD: https://pad.odoo.com/p/r.87a7ead0f01433057eaae2b3f0735dc5


--
I confirm I have signed the CLA and read the PR guidelines at www.odoo.com/submit-pr