Website editors get a more reliable page search experience when adding or editing menu entries. The update also improves save behavior and shows clearer messages when required information is missing or invalid.

Task: https://www.odoo.com/web?#id=27350&view_type=form&model=project.task&action=327&menu_id=4720
Pad: https://pad.odoo.com/p/r.164ececd9aef79bc377b847bacdb2430
Description of the issue/feature this PR addresses:

Current behavior before PR:

Desired behavior after PR is merged:
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This update introduces a redesigned settings experience for the Website app, making configuration clearer and easier to manage. It also includes supporting styling improvements and related accounting configuration adjustments that help align settings pages across the system.

New website settings by cbu.