### [FIX] website_sale: show categories/hide filters in /shop mobile

Before this commit, when the settings "eCommerce Categories" and "Product
Attribute's Filters" are set, neither of them are visible in mobile.

The expected behaviour in mobile is to display categories and hide filters.
The choice to hide filters in mobile is deliberate, and this is to avoid to
scroll too much in order to see the list of products below.

The cause of the issue is that both settings share the same DOM element
`<div id="products_grid_before">`. When the filters are activated, it hides
the DIV for very small screens.

This commit solves the issue by having two sub-elements of
`<div id="products_grid_before">`, namely `products_grid_before_categories`
and `products_grid_before_attributes`. That way, we can independently set
the visibility rules of each of these settings in the side/navbar.

Fixes #23864

### [IMP] website_sale: toggle visibility of product filters in /shop mobile

Before this commit, product attributes filters are hidden on small screens.

The reason of hiding them is to avoid scrolling too much before consulting
the product list below.

This commit enables attributes filters on small screens. By default, they are
not visible, but the user can click on 'Show Filters' to make them visible.
video: https://youtu.be/GlX_ad9SvIE



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