/tellraw hoverEvent accept nbt components

When creating a hoverEvent, it is currently only possible to display predetermined items or entities.

My suggestion would be to allow nbt components for show_item howerEvents (as long as they are valid Item tags):

/tellraw @s [{"text":"","hoverEvent":{"action":"show_item","contents":{"nbt":"SelectedItem","entity":"@s"}}}]

and similar to allow selector components for show_entity howerEvents:

/tellraw @s [{"text":"","hoverEvent":{"action":"show_entity","contents":{"selector":"@s"}}}]