NOTE: Whilst flutter supports plural-translations,
we are not using them for unitAmountDisplay,
because it is hard to choose the fitting one,
for doubles.
Similarily to categories and rooms,
the edit product screen is reused as a new-room screen,
which is especially easy, because the user is unable to select
the product id themselves.
NOTE: the dynamic value-unit input is still missing some "subunits"
The view product screen has links to the edit product page,
the view parent page (if available) and a not yet functional
view children screen.
NOTE: The parent product display should be restricted in width,
and the screen is missing value/unit information.
including the ability to
add item into the shopping cart and remove them.
The click events have been implemented,
however the routes do not exist yet.
NOTE: The shopping list item info sheet is still missing
the unit type and value
and some more advanced options, like deleting the item
