This change updates the web module to use Odoo's shared content caching setting for menu loading instead of a separate hardcoded value. It keeps caching behavior more consistent across the platform and reduces future maintenance risk, with no expected visible change for users.

use CONTENT_MAXAGE to define the max-age instead




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This change avoids cleaning up the same interface component children twice when a component is closed or removed. It reduces unnecessary background work and slightly improves performance without changing user-facing behavior.

This commit prevent from going through the widget's children twice when `destroy()` is called :
* once in `ParentedMixin`
* once in `Widget`