Removed unused bool documents[d].skip_me.
Assigned key sets to more meaningful array names.
Restricted posted geometry objects to type and coordinates.

I've found my custom 'EPSG' info in the data posted to
_list/bbox-filter/geojson.
Fixed filters[0].time converted to false unintentionally.
Stashed current document set into update_items().

If the filter takes all day long, at least the rest of the map still works.