This update cleans up the Enterprise web interface code and related mobile tests ahead of the next major version. It helps improve maintainability and consistency without changing how users interact with the product.

Linting `@web_enterprise` code before v16

This change removes unnecessary internal code in the Field Service Sales product view to stay aligned with recent platform updates. It should have no visible impact for users, but helps keep the system easier to maintain and less prone to future issues.

Adaptation to some changes brought by the third commit of https://github.com/odoo/odoo/pull/99294

The Engineering Change Order card view in PLM now uses Odoo's standard cover image action instead of a custom script. This keeps the user experience consistent while reducing custom maintenance work and future upgrade risk.

This is done by using the 'standard' set_cover action.
This allows to remove all custom js.

task: 2885757