Advances for #78731: We control the enabled state of the tool when creating the tool (so the button is enabled if we open the edition toolbar with a point layer selected) and when the login state changes (so if we have selected a point layer created while unlogged, open the edition toolbar and then log in the button gets enabled).
Fixes #78731:  Created a common class for the add point, add line and add polygon features, that can be configured with the supported geometry type when added to the edition toolbar.

Specific classes for these features are thus unneeded and removed.