Add "Open Feature in Mapillary" to the dropdown of a feature

[tordans]

It would be convenient if the dropdown had a "Mapillary" Link which would open the the Mapillary UI at the center of the way or on the node.

Right now, one has to open iD, add the Mapillary layer and search for pictures from there.

For a different project, I used the workaround to select the center lat/lng value of a way which is a good enough compromise to open relevant Mapillary view, see https://github.com/FixMyBerlin/osm-scripts/blob/22a6475fec9fb633604762ccebc42497a9413669/ZESPlus/utils/addCustomProperties.ts#L17-L23.