Post offices and related items need to be in the brands tree, not the operators tree

[bhousel]

This PR moves the post offices from the operators tree back to the brands tree.

This fixes the situation for Poste Norge and Post Office (and probably others) where they are really brands that have independently operated locations. This also more closely matches the current guidance on the OSM wiki for tagging post offices.

closes #5564
closes #5561
closes #5446

[1ec5]

To be clear, #5561 (comment) described an edit to the amenity=post_office documentation that should’ve had little bearing on amenity=post_box. Conversely, these features were originally moved from the brands tree to the operators tree in response to feedback in #4925, but that feedback was about amenity=post_box, not amenity=post_office.

I think the back and forth is because post offices and postboxes are being treated identically. But it seems like the expectation – most of the time – is that post offices need the distinction between brands and operators more than postboxes do. Contract post offices are a widespread phenomenon in many countries, but contract postboxes would be much more of an edge case.

(I did argue in gravitystorm/openstreetmap-carto#1023 that postboxes should be labeled based on their operators, but that was before I learned about brand and before it had become common on postal facilities in the U.S.)

[bhousel]

oh ok - If I'm reading your comment correctly, it sounds like amenity/post_box should remain in operators tree? That seems ok to me.

[bhousel]

I ended up reverting this PR, there is some investigation on #5613 and I'm now convinced that we can have a category like amenity/post_office that has some items in the operators tree and some in the brands tree.